Kates Playground Pool What Movie Is This? I Cannot Remember The Title.?

What movie is this? i cannot remember the title.? - kates playground pool

What is the movie where the husband and wife are each baby-sitting for children and only one case. the children in the pool and there the whole time or on the playground or the other. the end is a scene with a pedophile. What movie is it? I think Kate Winslet is in it, perhaps?