I don't have children so I cannot really offer advice on that. Different strokes work for different folks, really.
As for sleeping and adjusting to the night shift, I try to stay up as late as possible (into the wee hours of the morning) the night/morning before my shift. Get some room darkening curtains if you can, or use a sleep mask. Keep the room dark and cool. I always have to have a fan on for some white noise and to also help keep my room cool. Turn your phone off. I basically tell everyone that your 2pm is my 2am and they seem to understand. They know to only get ahold of me in an emergency. Sometimes I will take a Benadryl to help me sleep if I am trying to get back onto my night shift sleeping schedule.
As for coming off of it and going back to "normal people hours" lol, I come home and sleep for a few hours, wake up, go about my day and just go to bed earlier. Some of my coworkers will work all night and stay up all day and go to bed early in the evening. I couldn't do that. Also note that it is much easier to do this when you have your shifts clustered in a row. It's much more difficult to do this when your shifts are spread out throughout the week. I personally like to have my shifts together for this reason but lately that hasn't been feasible.
Drink coffee if you have to. I'm a coffee fiend, lol. Try to cut off your caffeine intake by 0100 or 0200 so that it won't interfere with your sleep later. If you feel like you're dragging by the time 0300 or 0400 rolls around, get up and go take a walk around the unit. Sometimes I will drink a sip or two of some coffee and that will help keep me awake. It won't interfere with my sleep, either.
Also, drink lots of water. It's so easy to become dehydrated because we're so busy caring for others that we don't have the time to take care of ourselves.
I also suggest putting on some sunglasses for the drive home. When light hits the eye it interferes with melatonin production, which is what your body produces in darkness and helps you sleep. Just please be careful if you have a long drive home. I'm lucky I only live about 8 minutes from where I work, but in the past I have had to drive an hour to and from work and that was very difficult for me after working 12 hours at night. I can't tell you how many times I dozed off and almost crashed into the median. It's very, very dangerous. In that case, bring some healthy snacks (like some almonds or grapes or something) and munch on your way home. Turn the music up, bring the windows down...whatever you need to do to help keep yourself awake during your drive home.
When I do get home, it's usually between 0730-0800. It depends, really. Some mornings I get home earlier, some I get home later. I'll take a shower then go straight to bed. I usually sleep until about 3 or 4pm but sometimes that isn't always feasible. If I can't sleep well, I'll get up and do whatever and then I can usually squeeze in a nap before my shift starts.
As for food, I usually take leftovers. The crockpot has become my best friend. I'm always too tired to cook when I'm on my night shift schedule so I have learned to make good use of the crockpot. Prep time is usually very minimal so I just throw in whatever I am making the morning of and when I wake up, dinner is already done.
I also love snacks. I take a lot of fresh fruit (bananas are a favorite, also apples, grapes, blueberries/blackberries/raspberries), maybe some string cheese, greek yogurt (I love both Oikos and Chobani), granola bar(s) (I like Kashi), some PB and crackers (or with an apple! delicious!), etc.