Based on the foliage, architecture, petal type, etc., my guess is that this is probably a parent, or more likely, a grandparent of Birthday Girl. It is too bad there is no parentage record for such an amazing rose. But this is my closest guess-timate. Strawberry Ice is likely the other parent. But, again, we will likely never know.

Edit: Turns out that a sister to Pink Wonder, Frenzy, was the grandparent.