R.D.
My FIL is a sleep walker... my husband is a sleep walker... his 2 little brothers are sleepwalkers... $20 says our son is a sleep walker! And coincidently, my middle child (from a previous relationship)... is a sleepwalker!
Point is, there's a very good chance, I'd say, of your kiddo possibly picking up the habit. Do you remember when you started doing this? Bring it up next time you're at the pediatrician, and keep track of what happened during the DAY before it happens, see if there's any sort of pattern (like if my daughter goes to bed 30 minutes later than normal, she WILL sleepwalk).
Best wishes :)