Not sure, but I've also been trying to limit mine. I especially try and limit before bed. It's really twitter that is my problem. I really don't follow many normal people, just sports, news, etc., but I still can't not look at the replies. I'll be thinking about something hours later and realize it was because I saw some nonsense on Twitter and realize how stupid it is that I'm still thinking about it.
For kids, i'm not sure. I try and limit it, but its fracking cold out and if my kids aren't on a screen they are yelling and bothering me. I also wonder if TV is better than an iPad? for some reason I think it is.