My partner (m) and I (f) are trying for our first baby. My partners mum wants the baby to refer to her as ‘mama’. She already has other grandchildren which do this, which makes her feel as though she’s justified in wanting this. Adding to this, my boyfriends family called his grandma ‘mama’ and his great grandma ‘great mama’. He’s a mummy’s boy and I feel bad breaking family tradition but I’m really not comfortable with this. I’m the bad guy in this situation and they keep reassuring me that there is a subtle pronunciation difference but I can’t hear it and saying I will ruin tradition and confuse the grandchildren if they all use different names to refer to their grandmother. They’ve made it clear it’s not open to discussion but I can’t get my head around it. AIBU?