Moral of the story... (SPOILERS)

Don't be freaking stupid!!

From the mother to the hubby. They both DUMB AF. First of all, why in the world would you trust this lady to look after your kid? She just lost her baby, she had some nasty accusatory things to say to you, and her husband has a few loose screws too. But never mind that, lets move on... After finding out that the lady was taking pictures, breastfeeding the baby, etc. I would explain to my husband in calm manner what I've seen, what I've found out, and that we need to get the phuck outa dodge. Even if it's difficult convincing the hubby, you'd at least keep your poker hand hidden, and that is "the ones below" don't know that you know. Instead, she goes batshit crazy and the whole thing backfires. Then again, we wouldn't have a movie if she used common sense, right? LOL!

As for the hubby, you just saw your wife stand next to a lake, and obviously you're thinking, "my wife is unstable, she might throw the baby in." You were sensical enough at that moment to ask your wife, "What do you need?" She then says she wants to move and you agree. That's great, seems like you're pretty smart. A phone ring, a business deal opportunity, your wife still looks unstable as hell, she even begs you to stay. But you go, "Don't worry, nothing's gonna happen." All of a sudden you dumb as phuck. LOL!

Seems like many events were contrived to force a dark ending, kinda like Eden Lake, another British movie with a contrived dark ending.