What do you call your bf/gf's mom and dad?

Anonymous
Do you call them by their first names? Mr/Mrs (last name) or do you call them mom and dad?

The reason I ask is because my brother has been dating this girl for a year and maybe a little over 6 months in she started calling my mom "mama" and sometimes "mommy" and it just bugs me. I feel like that's only appropriate when they're married. I don't know. What do you guys think?
First names only
I adress them by Mr. or Mrs. (last name)
Mom and Dad is fine
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What do you call your bf/gf's mom and dad?
15 Opinion