No brainer really! If you love your dog and want him to live a long and happy life, keep him away from any danger of being accused of hurting anybody or any other animal. No matter where you are - even in your own home.

I have a cute little West Highland terrier - read "Kid Magnet", and I put myself in between her and them each time they approach. She's never ever done anything to anybody, however you can never trust that a child won't poke her in the eye or do some other thing that could provoke retaliation in self defense. Even a warning non-contact "snap" could be perceived as "vicious". I would much rather take precautions than to have my very pampered, and loved pet, put down just because some idiot parent won't teach their child how to behave near animals.

So, if you love Megatron, be his best friend and protector. Leash him if kids are running nearby. Frustrating and unfair when at a dog designated park, I know, but better safe than sorry. Injury to a human = dead dog. Simple.