We keep trying to draft some manner of toot along the lines of, "We're birthday ponies!" but we're having a hard time making it clear that we are ponies having a birthday, rather than that we're ponies that people might request to have on their own birthdays.

To clarify, we are ponies having our own birthday. We are not ponies for your birthday; if you're rich enough to afford us for your birthday, we probably wouldn't get along in the first place.