It still bothers me that RTD clearly didn’t put as much effort into Martha and Donna’s backstories as he did Rose’s.
Donna gets one story about getting on a bus when she was told she wouldn’t get a holiday one year. Martha has:
I suppose she has a bit of implied backstory with her mother and sister (Francine seems to be a rather pushy parent, Tish thinks her sister’s a nerd)
but really, if you want a her backstory and the tale of why she decided to become a doctor, you gotta read The Story of Martha