Small group of 6 NCT group (but children now 5). Never my closest friends but I go along with whatever they organise most of the time.
One of them has a landmark birthday soon and wants to celebrate, we've all had to chip in £20 for a present (the figure has always seemed a bit high to me, but is usual for group presents for new arrivals etc, birthdays are not often celebrated), and as she can't do the weekend just before her birthday it's been brought forward another whole weekend, so the final date is 3 days after my birthday.
I now discover the chosen venue is a fairly posh/expensive restaurant that if I was going to spend the money on I'd rather spend it going out with DH with for my birthday.
So would I be unreasonable to say, great, as it's so close to my birthday I'll consider it a celebration for mine too?