My child’s first mom doesn’t like how I do my daughter’s hair. Help?

We have two children in open adoption situations.  Contact by phone, letters, pictures only, the birthparents live several states away and we have only visited once.   Our second child’s first mother and I have never seemed to quite hit it off.   I have tried several times to have conversations with her, and sent letters but she seems to not want to have too much of relationship with me. Which is fine, although not what I would hope for.  The issue I am having is over hair.   I am white, my daughter is AA.  Both her first mother and her bio grandmother have been v. upset about her hair.   I haven’t really been told directly what I am doing wrong with her hair, but I suspect they want me to straighten her hair(which at this time I am not willing to do).   A hot comb was mentioned in passing.   I was texted by the grandmother Christmas Day that she did not want any more pictures as they were “disturbing”.

I do my daughter’s hair.   It is not straight.  She is 4- I put it in puffs, double stranded twists, braids, etc.  Her hair is not as long as I would hope, but I *do* her hair.  It is healthy, well conditioned and thick, and her scalp is healthy also.   Her first mother is now asking me every phone call, every picture sent, etc about how I am doing with the hair.  Without asking, she has started to send boxes of hair products.  I have issues using the things she sends as they contain chemicals and things like sulfur which I do NOT want to use.   I use all natural products that don’t contain petroleum, etc.

The final straw for me came on Mother’s Day, after I had my daughter call and talk to her, and I sent pics. She texted me back saying she had SERIOUS concerns and I needed to contact her.   I have chosen to ignore it, which is the first time I have ever ignored any communication.   I consulted with somebody who is also a POC, and while she cannot speak for every POC, she was clueless about what could be upsetting after veiwing the very same pictures.   However, she did say that based on the region where she lives, her first mother may be very upset over the fact that my daughter has natural hair texture.

My question is- where is the line I should be drawing?  My daughters’ first mother never asks about my daughter herself.  What she likes doing, what she has been up to, how preschool is going, who her friends are, how was her birthday party, etc.  The only thing she ever inquires about is her hair and what I am doing to it.   I am feeling, frankly, attacked about it and I know I have a issue because those are my feelings.  But I also feel as if they are overreacting and having issues themselves. When we have discussed this on the phone before, I have always said I was open to any advice they wanted to give me, and I have explained in detail what I am doing for hair care.  I haven’t been given any feedback indicating that I should change our regimen.

Has anybody else had this situation?