NOTE: This spoiler was submitted by Ella
The movie opens with a voice-over by Penny Marshall about motherhood. We see a mom trying to get a child on the school bus. The girl clearly does not want to go and the mom, in her bathrobe, is clearly overwhelmed with getting the girl and her lunch on the bus.
Next, we see Sandy (Jennifer Aniston) in a towel. The youngest of her two sons, Mikey (Caleb Brown), is complaining that his older brother, Peter (Brandon Spink), left the top off the ant farm, and the ants got out. Sandy then is dealing with Mikey not having asthma medicine and Peter eating a donut when she does not allow sweets for breakfast. As she walks from the bedroom to the kitchen she realizes her ex-husband, Henry (Timothy Olyphant), has let himself in. The two have a good relationship. As he gets the kids to his car to take them to school, he tells her he wants to stop by later to discuss something important.
Sandy calls Jesse (Kate Hudson). They are best friends. Jesse and Sandy discuss the important thing Henry wants to discuss, and Jesse thinks that he may want to reconcile with Sandy. Sandy likes this idea. They hang up, and Jesse walks to her garage where Jesse’s sister, Gabi (Sarah Chalke), and Gabi’s life partner, Max (Cameron Esposito), are working on a float for the Mother’s Day parade. The float is a large pink womb.
The scene changes again to a bar called Shorty’s. Kristin (Britt Robertson) is talking to her boyfriend, Zack (Jack Whitehall). They have a baby together, Katie. Zack is a bartender and Kristin is a waitress there. Zack is a want-to-be comedian and is telling Kristin about a comedy contest that has a prize of $5,000. There are three rounds to the contest. Each round is on a different night.
Next, we see two girls and their dad at a cemetery. The gravestone is for their mother who was a Lieutenant in the Marine Corps. Bradley (Jason Sudeikis), the dad, says this will be the family’s first Mother’s Day without their mom. The girls’ names are Vicky (Ella Anderson) and Rachel (Jessi Case).
Next, Miranda (Julia Roberts) is selling her jewelry on a home shopping channel. Throughout the movie Miranda is shown on television screens and everyone seems to be wearing her jewelry. Obviously, her products are very popular.
Jesse is in her backyard. She is talking with Gabi about how this time of year gets her down because she has been estranged from her mother and father for quite some time. Her parents did not approve of Jesse dating a gentleman of Indian heritage. The parents do not know that Jesse married the gentleman, and they have a child, Tanner. Gabi says while she still talks to their parents, what she tells them is total lies, as they do know she is a lesbian and thinks Gabi is engaged to an investment banker named Steve.
Sandy and Henry are sitting on her porch swing. Henry tells Sandy he eloped. Sandy is surprised and asks with whom. His new wife is Tina (Shay Mitchell). Sandy is surprised as she thought they broke up a while ago. She makes some cracks about Tina’s age. Tina is in her mid-twenties. Adding to Sandy’s misery is Henry already told the boys as he dropped them off at school earlier in the day.
Bradley is at a gym he works at. He is no longer in the Marines since he lost his wife. Three moms from his older daughter’s school want to set him up with another mom. He says he is not ready. The moms ask about his Mother’s Day plans. He says they plan to ignore the day. They are about to hassle him but get distracted by Miranda on the television previewing her new products.
Gabi is Skyping with her parents, Flo (Margo Martindale) and Earl (Robert Pine). The parents are traveling in a recreational vehicle. They are prejudice with Flo making especially cutting remarks. Jesse is sitting next to Gabi, and it looks like Jesse wants to talk as well. She removes her wedding rings, but then mouths to Gabi, “I can’t do this.” Gabi tells her too bad and pulls Jesse in front of the camera. Flo says it is nice Jesse wants to apologize. Jesse says she is not apologizing; she is just saying hello. It is a short conversation.
Sandy drops the boys off at Henry’s house. Henry and Tina come to the door. Tina’s ring is huge. Sandy congratulates them both. Tina is wearing short shorts and a revealing top. She made amazing sugar cookies for the boys, and the boys follow Tina into the house without really saying goodbye. Sandy asks Henry to have Tina put on more clothes. Henry asks if they can have the boys for half of Mother’s Day since Tina is technically their mom too now. Sandy refuses before walking away.
Lance Wallace (Héctor Elizondo) is Miranda’s agent. He is looking to find someone to redesign Miranda’s set. Miranda's assistant suggests Sandy and a meeting is to be set up. There kids are playing and get Lance’s jacket wet.
Bradley is home watching videos of his wife. Rachel calls him to dinner and later asks him to go to the grocery store to get a list of things including tampons.
Zack is at the comedy club. His comedy sketch reveals he has been with Kristin for five years, and she still won’t marry him. He does well in the contest and advances to the next round. At home, he tells Kristin he really wants to marry her, and he won’t wait forever.
The next morning Sandy runs into Jesse and Kristin having a playdate with Tanner and Katie. Jesse introduces Sandy and Kristin and says Kristin is having cold feet about marrying Zack. It is not marriage that scares Kristin but the possibility of divorce. Sandy leaves and Kristin reveals she is adopted. Jesse encourages her to find her birth mom. Kristin says she has a name and address but has never had the courage to contact her.
Sandy goes to Mikey and Peter’s school play. Peter is in the band. Mikey is playing a lion. Tina comes and sits next to Sandy. Sandy is surprised to see her there. Tina mentions some fun plans coming up with the boys. Tina is not mean about it or making it a competition; she is simply excited to be a part of their lives. Sandy feels like it is a competition and says they need to set some boundaries and rules because she does not like surprises.
Bradley is in the grocery store. Sandy is in line behind him. They have an awkward chat. When Sandy leaves the store, Henry calls to say he is taking Tina and the boys to Paris. After hanging up, Sandy has a meltdown in the car about how she and Henry could not get to Paris in thirteen years, and Tina has only been married for five minutes. Bradley sees her fit, but she does not see him.
Bradley is coaching Rachel’s soccer game and gets kicked out for yelling at the ref. He and Rachel have a fight about how he is no fun any more, and she leaves with a boy she likes named Thomas.
Zach is at the second night of the comedy competition. He does well.
Sandy shows up to the Four Seasons to meet with Miranda. Sandy is late. When she finds Miranda, Miranda no longer has time and is now with fans. Sandy makes a scene about how she is late because she had to get asthma medication for her son, her car is slow; her ex-husband married a tween, and she ripped her shirt. Sandy has turned away. In frustration, she throws away her 3D design of the new set. Lance finds Sandy and says Miranda would like to see her now. At the meeting, Sandy apologizes and is scattered. Miranda is nice and asks Sandy about the tween her ex-married. Sandy shares about her life. Miranda reveals she took the career route instead of the family route. Miranda gives her advice about how accepting Tina will make her life easier. To her surprise, Sandy gets the job.
Max and Gabi come over to Jesse’s. They live next door. Earl calls via Skype about Flo’s Mother’s Day gift. Jesse is only half listening and is discombobulated as she is trying to get her wedding ring off, a picture of her family off the wall, and a more modest shirt on all at once. Earl says the gift will be amazing. The doorbell rings as the call is happening. Jesse yells come in. SURPRISE! It is MOMMA and DADDY! “Oh, that is not good!” Gabi and Jesse are stunned. Jesse in panic mode texts her husband to tell him, their son and their nephew to stay in the garage. Flo wanders into the kitchen where she meets Max. Who after being insulted by Flo, and despite Jesse’s best efforts to get her not to, introduces herself as Gabi’s life partner thus outing Gabi as gay. Flo and Earl real in shock. Seconds later Russell (Aasif Mandvi), Jesse’s husband, comes in and asks why he has to stay in the garage. Earl asks if he is the house boy. Russell says no he owns the house and asks who they are. They say they are Jesse and Gabi’s parents. Russell says that is impossible because the parents are in a dementia ward in Arkansas. Flo and Earl are also introduced to their grandsons. Lots of prejudice insults get thrown around before Earl and Flo storm out to their RV.
Russell packs his suitcase while calling Jesse a liar. He storms out with his suitcase.
Flo and Earl get to the RV to see they have a flat tire. They have to camp in Jesse’s front yard for the night as the tire cannot be fixed until morning. Flo is looking through old pictures of her girls, and we wonder if her heart is not as hard as it seems.
Russell has run away from his home to next door and is spending the night on Gabi and Max’s couch.
The next morning is the Saturday before Mother’s Day. Sandy throws a huge party with clowns, a petting zoo, a huge blow-up water slide, the works! Henry comes and is mad she did not drop off the kids on time.
Miranda is at a book signing in Atlanta. Kristin gets in line and says she is her daughter. We see Lance and Miranda’s assistant talking to Kristin outside without Miranda present. They do not believe Kristin is Miranda’s daughter. Kristin gives Lance a copy of her adoption papers and says she did not want anything, and she made a mistake by coming.
Back at the gym, Bradley is asking the three moms about the Thomas kid that Rachel likes. He hides from Sandy when she comes in for a yoga class because after the weird conversation in the grocery store and the meltdown in the car he thinks she is weird.
At the bar, we hear that Zack did not advance to the last round of the comedy competition.
That evening Bradley spies on Rachel as Thomas brings her home from a party.
Zack is at the comedy club repeatedly calling Kristin. Someone dropped out, so he made it into the finals. He has the baby with him and is getting scared that Kristin has bailed on him and the baby since it is not like her not to pick up her phone. Zack has to go on stage with the baby since Kristin has not shown up. The audience loves Katie. After the act, Kristin comes in and tells Zack she went to see her real mom. They recommit to each other. Katie and Zack win the contest and the $5,000.
In the morning, it is Mother’s Day.
Bradley wakes up and cannot find his girls. One of the three moms calls and says they are with her and not to worry.
Sandy’s boys bring her breakfast in bed and give her cards. Mikey accidentally gives her the card he made for Tina. Mikey says he will throw away Tina’s card and gift because it made his mom sad. Sandy has them crawl into bed with her and explains that she is just sad because sometimes it is hard to share what you love most. She says she will try to share more. She asks them to have patience with her. She suggests a plan to take them to Henry and Tina’s home later for an hour so they can see Tina and give her their gifts on Mother’s Day.
Earl and Flo are ready to go and never see their girls again, but the fuse for the ignition is gone. Earl has to walk a mile to get a new one. In the meantime, Flo goes to get the beer they left in Jesse’s fridge. She answers an incoming Skype call from Russell’s mother. The two of them bond over the fact that they were both expecting their children to marry someone of their own heritage. Flo finds her grandsons playing in the backyard and plays with them.
Sandy drops the boys off to see Tina. She does not get out of the car, but Henry thanks her for letting them come over. Tina is, of course, delighted to see the boys, and they are excited to give her their cards and gift.
Max leaves with the boys and the big pink womb float for the Mother’s Day parade. Jesse still has not heard anything from Russell. Jesse and Gabi are summoned to the RV to have one last talk with Flo and Earl before they leave.
Bradley sees the girls at the cemetery leaving flowers for their mom. Kim, one of the moms, has taken them to see their mother on Mother’s Day. He drives away before the girls or Kim see him.
Jesse calls Russell and says she is leaving and taking Tanner. They plan to live with her parents. Russell grabs Gabi’s pink bathrobe to put over his boxers and storms out to the RV. Once he is there, Jesse says she lied about leaving. She just wanted to get him to the RV so the family could talk. Russell is pissed and tries to leave, but then he hears his mother’s voice. His mom has been Skyped into this family meeting as well. He is still mad and tries to leave, but Earl pulls out of the driveway. Gabi says she just wants them to be a family and confesses that Charlie, her son, messed with the engine so Flo and Earl could not leave, but the tire was an accident. Earl is driving too fast and says the brakes are out. Russell drags Jesse to the floor to protect her, and they make up. Everyone is screaming, apologizing, and confessing all sorts of things. As they nearly hit mailboxes and everything else, Max sees them and chases them. So there is a huge RV followed by a huge pink vagina going through the streets. Cops enter the chase as well. Earl then stops the RV. The brakes were not out; he just wanted everyone to get along. The cops come and get everyone out of the van. The cops want Russell to get on the ground, but Flo and Earl stick up for him. Everyone makes up and because the pink vagina missed the parade they are just going to go to the park and have a picnic.
Vicky and Rachel come back to the house and find balloons and flowers. Bradley has set up a party to celebrate Mother’s Day and their mother’s memory. Other single moms and their kids enter the party including Rachel’s crush.
Sandy is out for a run and gets a call from a panicking Tina. Mickey is having an asthma attack. Henry and Peter are not there, and Mickey’s inhaler is empty. Sandy tells Tina to move Mikey to the freezer and have him breathe in the cold air. She then tells her where the backup inhaler is. Tina is scared but doing ok with Sandy’s help. Henry comes home, sees Mickey’s bad color, and scoops him up to take him to the Emergency Room. Sandy is still on the phone and says she will meet them there.
At Bradley’s party, he starts the karaoke. The girls join him, and he accidentally goes over the balcony breaking his foot.
Kristin answers a knock at the door to find Miranda with a gift. Miranda comes in, and they talk. Miranda was sixteen and in love. When she and her boyfriend told their families, they were pregnant the boy’s family moved the next day and Miranda’s family took her out of school for a year. Her mom shamed her about getting pregnant and told her she could not keep the baby. Miranda’s mom found Kristin’s adopted family. Miranda says she lost the two loves of her life her boyfriend and her baby so she concentrated on her career. Kristin introduces Miranda to Zack and Katie.
At the ER, Mikey is better. Sandy thanks, Tina and says she did a good job. Sandy gives Tina the nickname “Backup”.
Zack is at the bar. He sees Miranda on tv and turns it up. Miranda introduces Kristin as her daughter, and Kristin gets down on one knee and proposes to Zack. She says she wants to get married today since Miranda is only in town until tomorrow. She suddenly appears at the bar as the program was prerecorded. Zack says yes to the proposal.
Sandy goes to get candy for Mikey out of the hospital vending machines. The candy gets stuck. She tries to reach through the bottom of the machine to get the candy unstuck but ends up getting her arm stuck in the machine. Bradley and her two girls come by. The girls go to find a security guard with a key and Bradley gets her unstuck. She asks why he is in the ER. He says he broke his foot. He asks if she escaped the Psych Ward and is wandering the hospital. He tells her that his wife passed away. The girls come back and are delighted their dad is talking to a woman. Rachel insists Bradley give Sandy his business card. Sandy notes she just joined the same gym and looked forward to seeing him there.
At the park, Jesse, Max, Gabi, Russell, Flo, Earl, and the grandsons are having a picnic. Russell’s mom shows up too. She and Flo hug and celebrate that their plan to get everyone to be a family worked.
At the bar, the wedding is about to take place. Miranda is asked to hold Katie, but she obviously has no clue how to hold a baby. The wedding takes place with Lance officiating. (As a side note the ring bearer, and the two kids doing cartwheels are Julia Roberts’ super cute kiddos Hazel, Phinnaeus, and Henry! So watch for them!)
Henry apologizes for dragging the boys out of Sandy’s party the day before. Bradley comes by as he is leaving and waves at Sandy implying he will be looking forward to Sandy dropping by the gym.
We see the end of the wedding and Miranda is happily surrounded by her family.
Back at the park, Russell’s mom and Jesse’s mom take a selfie. That family is restored and happily loving their quirks.
The credits have bloopers so stay for those.