Today I was playing on us beginner and I was a 6 year old girl called rose sans when suddenly I couldn’t do anything and then my game started to glitch out, then my screen went to black, then for some reason I was born as a baby in the black screen then got yellow fever then died, when I went back into the game it had a family tree of me as the baby that said starved to death, when I went back 1 family I saw me on the other one and it said still alive
Please check your network. 
This probably because your network. But it’s kinda weird if you born as girl then suddenly becoma a boy.
I had this glitch or something similar happen once.
My best recommendation would be to update your device’s software to the latest version.