I agree it would strike suspicion in me, but maybe not so in others if he never behaved inappropriately in anyway and they all played in a group in the middle of the trailer court. The guy lived there for many years, so if he was outwardly inappropriate I would hope the neighbors would put a stop to it. There is a difference between playing outside and him going inside to play dolls or something with one of the kids. A known neighborhood adult, engaging with multiple children building a snowman in an open area is not unheard of. I am hypervigilant because I read here and because of life experience.
So far through MSM, he is just looking like the once again, harmless neighbor.
What was going on in his mind is not something anyone can predict and because it appears, he was a well known neighbor, he would have a established trust with others in the neighborhood, including the kids.
Sadly, it would not be hard for him to figure out a way to harm a neighbor child no matter how watchful a parents eye is.