3D Paper Folding 01

My brother gave me this 3D Calendar as my birthday present.  He used a piece of thick fancy card, printed it, cut it, folded it and glued it.  It’s creative and I like it.

 3D Paper Folding 02

He also gave me a small empty 3D birthday box to me which was created by him also.  Thank you, Clement.

Can you guess which day is my birthday?  Give you a tip, the day plus the month is equal to nine.