Yes, but there are certain events that can transpire in the womb, the result of which the baby born is neither male or female, and the doctor has to make a desicion about the gender of the baby. When the baby grows up, they are both male and female, and may decide to be the opposite of what is written on the certificate. I saw a TV program about it. The baby was born "male", but was raised as a boy/girl and chose to be a girl, and they needed a court order to change the certificate so she could get married
It does happen.
And besides, who the hell makes up a name such as "Jemma Galbraith"?? If you make up a name, you put something generic, such as Alex Smith or something. I believe that is your real name, or you are more devious than any of us imagined.