We also had the same thing with our son in the third grade - he played with a boy from the same class, and then he started to ignore him after the holidays. My husband and I just talked to him that not all friendships last and helped us find other guys in the choir. Children forget quickly, but it is more difficult for adults not to interfere.
My daughter and I had a similar situation in the fifth grade – we were playing with a girl from the neighborhood, and then she just stopped responding to messages. We told her that not all friendships last forever, and we took her to a knitting class, where she made new friends. Kids forget really quickly, and we moms spend weeks wondering what we did wrong.
