I've seen plenty of bias, but I won't pretend I've ever really experienced it.
The closest I've come is as a single dad. People often assume I'm a babysitter; or my parenting obligations are anything but obligatory; or that I can't love these boys out loud, openly, in a profound way. Which is absurd at best, insulting for sure, and a dangerous lesson to instill in kids at worst.
Anyway, check it out. Good stuff.