What are the genotypes of the parents? I'm guessing it's Yy and yy, but I'm not exactly sure.

Well since the capital letter is dominate and always takes power and the lower case letter is recessive doesn't take power. It would be 50%.
The answer would be Yy and yy :D
In hindsight, that would remain the same. I'm sorry for the late answer but yes, it's Yy and yy.