How do you tell your parents or in-laws to abide by your hair rules with your children?

So most people that know me well know my mother hates me and my sister’s natural hair. When we both went on our perspective natural hair journeys she told us we lost our beauty when we big chopped. She also said that we will never find a man or get a good job. Then when I started dating my husband and I told her he likes my hair she laughed in my face and told me he was just saying that to get me in the sack. He couldn’t possibly like my real hair. Even though we are married now she still thinks he’s lying about liking my hair. So one day we were having a conversation about kids and she said you’re going to perm your kid’s hair right? I told her no. She got upset and said I should force my kids to have a hard life. I told her they will be fine. Then she said half jokingly. “Well if I ever get to keep your daughter for the night I will get her a perm when you’re not around.” I said mom you’re not serious right? To this day I’m still not sure if she was joking. I kept saying if I ever have a girl it’s my child and I alone decide what her hair does till she’s old enough to make that decision. But my mother seemed to not understand that. Now fast forward some years later and my married big sister has a daughter. Watching her relationship with her in-laws has raised some new questions for me. How do you relay a message without ruffling feathers or starting a argument with the in-laws regarding your child’s hair care. Now my sister is really strict about what my niece eats and what diapers she wears but when it comes to the in laws she just let’s stuff go because if it makes them mad it makes her husband mad. It’s a really delicate situation. If I put a pic of her up on Facebook I get yelled at but if they feed her greens before she has teeth she lets it go. So the situation that got me thinking about this is ongoing. My sister, and I know now that if you put rubber bands in your hair it will get tangled up, pull it out, and break it off in pieces. However; even though she told the in laws not to put them in her Child’s hair they continue to do so. Even when she provided them with cloth hair ties they discard them and return the child with rubber bands in her hair. We buy more cloth hair ties. We put cloth ones in her diaper bag. She comes back with rubber bands. This has happened over and over for the last year till she told me to drop it. Then one day my niece came back to us with slightly straight hair and a burnt smell in her hair. It appeared someone had tried to press her hair. My sister said it might be because his family smokes, and the smell got in the babies hair. Like that’s better. Any who She’s 2 so I got upset. No 2 year old should be getting a press and curl. My sis ask them if they presses it and they said no so once again she said drop it because her husband thought she was calling his mom a lie. Then one day his sister picked up the baby and said y’all need to get this child’s hair together. It was in a twisted out like Afro. I thought it was cute seeing how my hair was the same way. This just keeps happening, and it makes me wonder how I will handle this type of situation when I have kids. It seems like both sides have no idea how to truly handle natural hair. My mom always calls me to do the baby’s hair when my sister is busy. She does not know how to braid or twist and when I try to show her she doesn’t seem to have the patients for it. This is probably the same situation with the mother In-law. They are both from a different time period with a different mindset and unwilling to change or consider that times have changed and people’s minds are different. They probably think it’s a fad like in the 70s to wear your hair out, and it could be. However; I’m still going to rock my hair popular or not and I plan on teaching my future daughter how to love and properly care for her hair. If I ever end up in this situation, I always said I would go off and say you can’t keep the child anymore till you abide by my rules. I’m not letting anyone step over me in regards to how I raise my child, but would I really do that? Probably not cause I’m a peaceful person. Still how do you stand firm on things you want for your child without there being a huge upset? I hope I figure this out before I’m in this situation myself. Maybe I won’t ever have to go through this. I’ve never had the hair conversation with my mother-in-law cause it was never an issue. I let her do her she lets me do me. She’s never made a side comment about natural hair or how she does not like it, so I would assume it does not matter to her. She seems like the type of person that does not judge based on looks like most people I know. M My mom thinks my mother-in-law probably does not like my hair but has never said so to be nice. I asked my husband and he said that’s not true. So for right now the question of how to handle this situation lye dormant in the back of my mind till I’m wiser, and a little better at conflict resolution. What are your thoughts?