When we moved into this neighborhood, The Rabbit was already 2. Believe it or not friendships had already been forged. For the 2-year-old's.
So when she started pre-school, there were many birthday parties The Rabbit was not invited to. When her third birthday kicked in later that year -- I invited everyone in her class, and even the children she played with on the playground. It was a wonderful free-for-all - and she had a blast. It helped to meet parents too -- and start getting involved in the "groups."
Unfortunately, I still find this whole birthday party situation troubling. Especially when I know the Rabbit hasn't been invited -- and when I assume the other child is a supposed good friend.
Now, it's a given. We have playdates, dinners, our own events where we don't invite everyone. We just can't. But I still can't shake the feeling of anger when I perceive The Rabbit's been slighted. So what do I do? Nothing. I just consider it more excuses to drown myself in extra jam in the morning.