Both my parents had blonde hair as a kid, which then darkened to brown by adulthood. Mine's still blonde (my mom's was brown by now, I don't remember about my dad), so I'm not sure what to say about that.
My mom's side of the family all had straight or wavy hair. My curly hair definitely comes from my dad. He probably has 3a/3b, if not completely 3b curls. He keeps it a bit too short to tell completely.
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