My husband is the only boy and his sister has 2 girls, and he already hasa daughter...but we are having a boy!
Sperm determines gender, but the acidity of the vagina and timing if intercourse can make the chances if one sex more favorable. Does it always work? Nope. Just because he has two girls. Doesn't mean that he can only produce girls or that your odds are higher. It's all 50/50.
Sperm does has big role in gender but it can not be predicted what are the odds... All u cn do is wait n see in ur u/s what u r hving... Best of luck...
I doubt it,its still 50/50.