For background, there are about 15 kids in DS' class at school (rural primary), but he is close friends with 3 other kids. They go to summer school together, and usually if there's a group activity organised by me or one of the other 3's parents all 4 kids will be included.
On Friday DS came home from summer school all excited and nagging me to check my messages from his friend's mum as this boy (I'll call him Jack) was having a barbecue on Saturday for his birthday and there should be a invitation. I checked and there weren't any messages. It turned out Jack wasn't at school on Friday and DS had heard about the BBQ from one of his other friends, who apparently had been invited. I didnt know it was Jack's birthday so assumed that the other child must have misunderstood and he was just having a BBQ at home with his family.
Except of course there was a party, for Jack and the other 2 only; the photos are on FB this morning labelled "Jack and his besties" and "the happy trio" and things like that.
I am a bit shocked as I always considered Jack one of DS' best friends and if the situations were reversed I would have invited him without even thinking. DS hasn't fallen out with Jack in any way and I can't think of anything I've done wrong either. The only explanation I can think of is that since I've started working full time again I don't see so much of the other parents; I no longer do the school pick up, for example. But surely this doesn't affect the fact that our kids are friends? DS is confused and upset as he now knows from the others that there was a party and he wasn't invited.
DH thinks we should get Jack a belated present to underline that he and DS are still friends and leave it at that. I'm not sure what else I can reasonably do but I still feel unaccountably hurt by the matter. Am I being over-sensitive?