Fraternal Twins

Alissa
I'm curious....
Fraternal twins is more likely a heriditary thing. And identical is just a sheer chance. 
Fraternal twins is when 2 eggs are released and fertilized. 
So why the heck do people ask the men too if twins run in the family?? 
Isn't it more the women's heriditary history of twins what causes it. 
I know there's more factors in twins. Like age and  in vitro. 
And with indentical the one fertilized egg splits so maybe the sperm has something thing to do with it. But from what I understand identical twins isn't  heriditary. Just a miraculous thing that happens. 
I am definitely mumbling on and on as I'm typing this 😂
I'm having boy/girl fraternal twins. And I'm 26 weeks. 
My girl is measuring just right on track and my boy is measuring 1 and a 1/2 weeks ahead. I wonder if they were conceived on different days 😊 it's possible!!👶🏻👶🏻