They certainly can
They sure can get worms from the sand box. Cats will use these sand boxes for their litter and your kids get in there playin sand getting in their diapers or underwear or eatin the sand ewww.. So if your child are scratching at their butts .. What you do at night I know this is sick you get a flash light this is when the child is sleeping the worm comes out of the childs butt and when it does that it lays it eggs for more worms .. When you see this make a Doctors appointment the doctor will give you pills for the child ,maybe some cream for their butt