I hear "Your Mom" a bit too much in my house also.
And my mother was over this weekend. So whenever my daughter started a reply with "Your Mom", my mother said "Yessssss". Stopped the conversation immediately.
Not Yo Momma jokes - this is the latest rage in kid insults. "Your Mom" does xxx. Not Yo Momma. I have been reprimanded for turning these into Yo Momma jokes.