Is There Methods To Increase The Chances Of Conceiving A Girl?

No question is a stupid question??? well, i recently got into a debate with some female collegues. I live in Eurasia where people tend to still be somewhat folkloric. A friend of mine is seeing a doctor currently because she already has a boy and would like a girl this time and ( i was told) that since it has been 7 years since her last childs birth and he was a boy and now that her blood has changed she will be more likely to conceive a girl. I laughed and tried to explain the simple, girls have an X, men carry X and Y, and it just depends on which fish swims the fastest as to weather you get an X or a Y. They assured me that while I was right, that there are measures that can be taken to help improve the chances of a boy or girl. They treated me like I was uneducated in my own body because i had never heard of such things and i began to doubt myself and my education. So... my question is, is there a way to help a woman improve the possibility of having a boy or girl or is it all dependent on the man.