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Gender only has to do with your DH's side of the family as he is the one with the X and Y chromosomes. Each sperm is either an X or a Y. You only have eggs which are all X. So if boys run in your DH's family, then you do have a higher chance of having a boy. (That's why it's so tragic that Henry VIII beheaded his wives for not giving birth to boys. It was his fault not theirs!) Whatever gender affinity your family might have will be passed on to your sons but has nothing to do with your pregnancy.
Only fraternal twins are genetic as they result from releasing two eggs. Since that is the case, it only has to do with whether twins run in your family since you're the one releasing the eggs. However, any daughters you might have will have a compounded chance of having fraternal twins because of the influence of both her parents. Identical twins are just random and result from the fertilised egg splitting.
I hope that helps shed some light on the situation.
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Actually, the woman's vaginal environment can kill of X and Y sperm, so it isn't all male-dominated. Plus the woman's body can spontaneously abort a male/female foetus: this often happens before the period is even late, so most people who have this assume they're either a day late or that they didn't conceive that month. Only with early HPTs are more of these cases coming to light.
Men have both X and Y sperm, they don't make more of one sort, although men can also kill off one sort or another before they let them loose on the world.
