Another "Help me find this children's book!" thread

[NYCVeg]

My sister reminded me today of a book we loved when we were younger. A little kid thinks he's getting a surprise party and keeps talking about it...but then his parents convince him he's not? Or something like that...but he gets the party in the end. That's hopelessly confused...sorry!

Any guesses?

[Groovy Mom]

Aww, hope you find what you're looking for. I searched for YEARS for a book that I could just barely remember as a kid and finally found it. Best wishes.