So, am I being an ass and an overprotective helicopter parent and just a mean ole bugger who cannot see this kid is hurting and just needs some friends, no matter what age?
Or, am I being properly cautious and need to think of my own kids at all costs first??? After all, 1 13 year old hanging with an 8 year old sends red flags up all day, notwithstanding the circumstances.
They're your kids, you'd protect them with your life. Keep an eye on the situation, casually ask your children what they do with the 13 year old, what he talks about, etc. Give them advice as to how to get out of an uncomfortable situation and where to go for help if necessary.