“All happy families are alike,” the famous first line of Anna Karenina tells us. “But each unhappy family is unhappy in its own way.” The opening scene of this heart-on-sleeve American indie drama gives an almighty – and none too subtle – hint as to which sort of family is going to be the subject here. A plumber is in the basement of a family home in Chicago peering with a spy camera into the pipes. Something is rotting under the house: a rat! Worse, the ancient creaking pipes might collapse at any moment.

The house belongs to out-of-work actor and scriptwriter Graham Landry (Josh Radnor); more accurately it actually belongs to his successful older brother Will (Rob Huebel) the star of an outrageously awful hit TV series. It was their childhood home, bought by Will from their parents. Now only poor, stuck Graham – still sleeping in his childhood bedroom – lives there. But for a couple of days, the entire family gathers under one roof. Will has been accused of misconduct on the set of his show; their mum Sue (Becky Ann Baker) is groped by her boss at her retirement party, while dad Roy (John Ashton) is gambling.

All Happy Families is a film with a few too many storylines, none of them fully explored. It’s easygoing and likable if not-quite satisfying, getting by on the natural and relaxed performances. Baker in particular is warm and wonderful as mum Sue, and there’s a lovely, tender scene with her and Will’s teenage daughter (Ivy O’Brien), who has just come out as trans. In the end the film’s message is perhaps more intricate and subtle – and truthful – than it first appears, with its portrait of a family that is both happy and unhappy, each in their own way.

• All Happy Families is in UK cinemas and on digital platforms from 14 March.