Open Question: How do you know if there is a pedophile in your family? What would you look for?

Okay, this is embarassing but I rather be safe than sorry. I suspect my father of being a pedophile. He works as a school bus driver. He has a basement full of toys, however only 5 grandkids in total who dont visit or come around very often. I tried doing some research but theres no sure way of knowing. I have a 3yr old and a 20 month old. Im scared cuz its my own dad but i dont want to risk my kids & I hope Im not overreacting! He forces hugs & kisses on my kids and trys to get them alone. He nibbles on their ears with his tounge, I find it disgusting. He doesnt do it around my husband only me. My mother doesnt say anything either! What do you think? Seriously! I dont visit very often because of it.