Pre-1977. American, I think. Young child goes missing, parents join peer support group, get a life. Child returns, parents are too caught up in the group’s social whirl to notice/care. What’s the name of the film?
Taking Off (1971)?
Great work - that’s it! Thanks Chisco
In the 46 years since I saw it, I’d forgotten the child was a runaway teenager but the rest was more or less correct.