Painting

From the backseat of the car after picking A up from preschool:

A: I painted a picture of me and D. We were walking and you and Daddy are walking behind us. I am yellow because my favorite color is yellow and D is blue because that is her favorite color.

Me: I thought your favorite color is pink?

A: No, it's yellow.

D: I don't like pink anymore, it's too girly.

A (to D): So, you're boy-y?


Yeah, how come girly is a real word, and boy-y is not?