I'm multiracial and i don't have the "mixed chick hair"?

I'm nultiracial, ny parents are both from jamaica. My dad is black jamaican. My mom is half chinese, 1/4 black and 1/4 white. My mom has really long, thick hair and its really curly. I had really long hair too until i discovered relaxers......(worst decision of my life btw.) but i've never really had really curly hair like my mom. Is this usual or is it just me????