Is a ball phython an okay pet for a 5 year old?

I have a 5 year old and a 2 year old and we have a ball phython. I have been getting a lot of crap from my kids grandparents about having a snake around my kids. They think it's the worst thing to have in my house and even refuse to come over until we get rid of the snake. He has never bit them or even striked at them and he just crawls on them and does his own thing when we take him out. I can't stand cats and dogs, we tried having a dog and the dog kept attacking my 2 year old and the snake has never made a movement towards the kids! Is this an okay pet for them? Should I just tell their grandparents to buzz off, that I like the fact that my kids have exotic pets at a young age? (they also have a tarantula..)