It was Starwitch's writing, who is from Tennessee. She prob wouldn't mind it being edited, but you could ask her. I don't think it was meant to be insensitive nor disrespectful. "Your mama (or daddy)..." this or that is a common figure of speech in the Southern United States region. In fact, I always found that part amusing every time I read over it, since I have a lot of Southern relatives who spice their language with that.
Like, say you're standing in front of a TV, blocking someone's view. A Southern person might say to you, "Hey, now your mama wasn't a glass maker, was she?!" lol They say things in a round about way in the South, lots of allegories. I could see how it could be construed differently than was meant by someone not familiar with the colloquialisms of that culture, and with just letters on a screen minus the intonations and mannerisms that would have gone with with the spoken words.
I see you're from the UK, fieldmouse. I had the hardest time getting used to the common UK saying, "take the piss." I kept envisioning someone sneaking off with a urine sample, lol. And just this morning, a UK acquaintance of mine said when she and her son returned from holiday, she felt like she was "back in a crisp packet." She kept saying that over and over, and I was like, what the heck is a crisp packet
?! haha I finally had to Google it. A lot of things she says I just have to Google.
Language can be fun, but sometimes it's easy to misunderstand the meaning and intention behind what's said when it's online.