P.G.
Hi A.!
Your son is no longer the age he was when he started, and just like your son has grown, so have those same children he used to play with 2 yrs ago.
The days are gone when it was easy for him to make friends, and maybe the same kids that "played with him" are no longer there- its time to make new ones. This happens with everyone, even adults. He is just going through that phase of becoming 5 and becoming older. He will be fine. I mean, life is not always going to be easy and making friends will take some work- he has to learn this too in kindergarten. Take care and believe me - this too shall pass. God bless.