Not my family, obviously, but I felt it'd be interesting to post the stats here.
From Margo Dydek's (born in the 70s, in Poland) family:
Father: 201cm, 6'7 - Former Basketball player.
Mother: 191cm, 6'3 - Former Volleyball player.
Margo: 218cm, 7'2
Older sister: 201cm, 6'7
Youngest sister: 198cm, 6'6
This is a family of obviously exceptional genetics for height, but the two other sisters were no taller than their father, even despite the mother's height being more standard deviations above the norm than her father's.