I am not willing to step in front of the party train. D13 and her friends are too excited. However, D13 has also expressed a desire for an expensive birthday present. I am going to tell her that since we spent so much money on the party, we cannot afford to get her the present.

And I am striving mightily to resist the temptation to say "I explained to your mother that we only had enough money for the party or the present, but not both. When I heard you guys talking about the party, I assumed your mother has explained that to you, and that you had chosen the party. So sorry for this misunderstanding. Next time I will make sure we are all on the same page. But that doesn't change the fact that we can't afford to get the present you wanted."

When you can see it coming, duck!