Oh yeah, I meant to add that identical twins are a fluke anyway...
Fraternal twins tend to 'run' in families on the mother's side, when the mother ovulates and releases two eggs at the same time, one from each ovary and both get fertilized. That is passed from mother to daughter.
That being said, I still made sure my doctor checked REALLY close for twins. Sasha's a twin, and I know it doesn't run on my side but I still had that at the back of my mind...lol!