A toddler carries his little potty out in front of the house so he can try out his new-found skill in public. Twice. Plus another time when the contents of the potty are first displayed for the family and then kind of accidentally tossed onto one of the relatives. This is pretty much the theme of “This is Where I Leave You,” one of those estranged relatives gathering under pressure movies that tries to put the “fun” in dysfunctional.” It’s pretty much great actors trying to make sense of characters who are continuously inappropriate, unpleasant, and miserable, with boundary issues that make Russia/Ukraine seem manageable. And they almost succeed.

Jonathan Tropper wrote the screenplay based on his novel about four siblings returning home for their father’s funeral. Their mother Hillary (Jane Fonda) is a family therapist and the author of a best-selling book on child development that (boundary issue alert) revealed many embarrassing details about the siblings and is now celebrating the 25th anniversary of its initial publication with a re-release. She is given to wildly inappropriate revelations about her sex life with their father (another boundary alert), and showing off her newly enhanced breasts.

She tells her four children that their father’s last wish was for them to observe the Jewish tradition of sitting “shiva,” a seven-day period of mourning where the family stays at home together and receives visits from those who wish to pay condolences.  They understand that “it’s going to be hard and it’s going to be uncomfortable, and we’re going to get on each other’s nerves.”  But, Hillary says, they have no choice.  “You’re grounded.”

They try to protest, but reluctantly agree. Paul (Corey Stoll) is the only one who has stayed in their hometown, the responsible brother who took over the family business, and married Annie (Kathryn Hahn), who is struggling with fertility issues. Wendy (Tina Fey) is married to one of those guys who is always on his cell phone talking about some big financial deal. She has two children, the aforesaid toddler and a baby. Judd (Jason Bateman) is in freefall, having just learned that his wife has been having an affair with his skeezy boss (Dax Shepard), the host of a shock jock radio show called “Man Up.” And then there is Philip (Adam Driver), the irresponsible baby of the family, who arrives in a Porsche convertible, with a new girlfriend named Tracy (Connie Britton), who is much older and a therapist.  You don’t need to be a therapist to figure out that there are some mommy issues there.  Everyone but Phillip is aware that Tracy is way out of his league and he does not deserve her.

The three out of town siblings all encounter past loves.  Wendy’s is Horry (Timothy Olyphant), who was brain-damaged in an accident and still lives with his mother Linda (Debra Monk), Hillary’s neighbor and close friend.  Phillip sees Chelsea (Carly Brooke Pearlstein), who looks, as Tracy notes, like a Victoria’s Secret model.  And Judd sees Penny (a terrific Rose Byrne), living back in their home town and teaching figure skating.  Each presents temptations as the siblings struggle to make sense of their choices, and struggle even more to communicate.  “Deflecting emotion with logistics.  Nice.” “It’s what we do.”  Some secrets will be revealed (though not always intentionally) while others are protected.

Tropper’s screenplay is better than the book because we are not limited to Judd’s depressed narration and because it corrects what I thought was a mistake in the final resolution of Judd’s relationship with his wife.  And it is helped a great deal by performances that give the characters more believability and complexity than the book did.  But director Shawn Levy (“The Internship,” “Night at the Museum”) has always been stronger with broad comedy than with narrative, romance, and sentiment, and this storyline plays into his tendency to meander. Are we supposed to laugh at the Altmans because they are so awful or sympathize with them because all families are crazy at times? The bad choices, lack of respect, and wild swings of character keep us distant from the characters, despite the best efforts of the terrific cast.

Parents should know that this film includes very strong and crude language, sexual references (some vulgar) and explicit situations, nudity, adultery, drinking, smoking, marijuana and pharmaceuticals

Family discussion: How are the Altman siblings alike? How are they different? How do you feel about “complicated?”

If you like this, try: “This Christmas” and “Flirting With Disaster”