As for Leia being the youngest Senator, I believe she was elected in her late teens, whereas Padme says in "Clones" that they 'ammended the constitution' to allow her to serve multiple terms as queen, so she was probably 20 or so when she started.
As for Leia being the youngest Senator, I believe she was elected in her late teens, whereas Padme says in "Clones" that they 'ammended the constitution' to allow her to serve multiple terms as queen, so she was probably 20 or so when she started.