Alzheimer's Disease and Ehlers-Danlos Syndrome, haha. The Alzheimer's isn't early onset, but it hit my dad, his mom, and her mom. It's hard to tell which side the EDS came from, but I suspect my dad's side. My ex & I both have EDS, and so does my daughter, but it's quite manageable for us.
On my mom's side, heart and blood pressure issues reign supreme, at least on the less-happy side of things.
Appearance-wise, on my dad's side the men are tall and lean, and I take after them. My brother tends more to my mom's side, which tend to be stockier and freckled.
Speaking of tall and lean, my daughter is too, and she has my blue eyes (I was the only one in my family to win the blue-eyed lottery, everyone else's are hazel). She also has my slightly-off and punny sense of humor, but I'm guessing that's nurture, not nature ;)