Congrats!!!
Forget about the children I almost fell into the stairwell (LOL), only kidding about forget the children adults have to be careful too. Since I almost did that I make sure I put down the cover that slides down over my stairwell. Look into this or cut a board and cover it with carpet. My MH does have a dead bolt I am sure you can install one easy yourself.
Good luck, my kids are now 14 and 20 and they love to travel with us, especially when we go the the football games, a MH makes for good tail gating.
Congrats again and good luck.
Colleen FL