All Yours (2016)

Matthew made a fortune selling his firm a few years ago and just returned from a long yacht voyage. His tycoon father, who wants him to take over the huge family firm but fears him immature, convinces him to prove himself as a nanny for family friend Cass, a widowed mother of two and driven attorney: her mother has exhausted all candidates agencies can provide, as her rascal son and daughter scare them off in no time. Matthew however enjoys the challenge and the kids, acting rather as a big brother, and taking Cass's absurdly elaborate time schedule with a sack of salt. He wins over everyone by proving less obsession makes more fun and results.