Juro has some pretty good advice about covering up. I bought a long sleeve shirt of that supplex material in part to keep the sun and bugs off me. Wearing high concentrations of DEET seems to make me feel a little lightheaded, so I try to avoid it, but when it is neccesary I have found that Ben's insect repellant works well. The Ben's that I found has only a 19.5% DEET concentration, and if I remember correctly I read a report that anything over that amount doesn't help keep the bugs away. If others have different opinions, then I really can't argue - I just know that I hate to wear the stuff, so I try and spray my clothing (hat, shirt, etc) and not my skin, and it seems to work OK.
I'd probably look for other stuff for kids if you have any.
Have a good weekend,