We've all heard the adage that it takes a village to raise a child, but considering the state of villages these days, it could be the other way around. A case in point is "What We Did on Our Holiday," in which three kids unwittingly cure the ill will, pretensions and animosity among the adults in their family and consequently save their parents' marriage. (Now, if only they could get around to ending world hunger and climate change.) Hats off to their performances, and directors Andy Hamilton and Guy Jenkin, for keeping this film from plunging headlong into cutesy-land — most of the time, anyway.

"What We Did on Our Holiday" is based on a British TV series (by the same directors) called "Outnumbered," and by many accounts the screen adaptation ups the ante in terms of star-wattage and production values, giving it a glamorous sheen that was absent in the series. Which is not all good: The film could have done with more cozy homeliness and the sense that we, on the other side of the screen, are all in the same stew of family problems, marriage woes, aging parent issues, unmatched socks and all the rest of it. But the characters here look as though their feet have never touched anything but red carpets, with hands gracefully circled around champagne glasses. Consider the central cast: Billy Connolly as the family patriarch, David Tennant ("Doctor Who") and Rosamund Pike ("Gone Girl") as his son and wife. British comedian Ben Miller is the other son, and he offers a bit of down-home humor, but otherwise, upper-crust ambience prevails.

Still, "What We Did on Our Holiday" is very watchable, mainly because the aforementioned three grandkids (Emilia Jones, Bobby Smalldridge, Harriet Turnbull) are naturally superb without being coy. They're often razor-sharp and spot-on, in the sort of disinterested, unintentional way of youngsters. This led me to ponder why humans have to get older and turn into dreaded adults. The only advantage they seem to have over the 10-year-olds in the story is the freedom to enter a pub to drink themselves into oblivion, which — when you think about it — is not much of an advantage.