I don't use number and letter hair type descriptions because I don't get them (still after 10 years on the hair boards)
My hair is my dad's hair. No one can tell now b/c he's bald though. He had the thickest waviest blackest hair I'd ever seen. I fell in love with DeBarge b/c they had hair just like my daddy's. When we were kids, we used to braid his curls. Mine was thick but it's getting thinner with time.
My mom's hair is fine, fine, fine. When she wore an afro, it blew in the wind. She's been natural all her life and when she wants to wear it in a straight style, she pulls it into a ponytail, lets it dry, and adds some curls for body. I used to want her hair but frankly, it's too fine to do anything with. It never grew long because it's super fragile.
My dd1 is my hair twin and my dd2 is a combo of me, my mom, and my husband.
Genetics is a crap shoot.