I might be being over-sensitive rather than BU but...
We've been invited on hols with friends of ours (couple one) and friends of theirs (couple two).
Each couple has one DC, all are roughly the same age and at the time of the holiday will be around three.
So far so good but here's the rub:
The DCs of couples one and two attend the same nursery and are firm friends (it's v v sweet to watch), as a result they always play together.
At other events our DD has been v much on the periphery of this but as she is only two-and-a-bit right now there's little actual play and more just parallel play so it hasn't really mattered at all.
Will this still be the case by the summer when they are all three though?
If so, will DD be old enough to feel "left out?" And will it even matter since DH and I will be there to entertain/play with her?
I think IABU/over-sensitive because I had a terrible time with a group of girls "leaving me out" when I was at little school and I remember it felt awful - but I was obviously older.