She was a companion of the Fourth Doctor, who was randomly left when he went to Gallifrey. Who eventually ran into the Tenth Doctor at a school, which they blew up. A few months later she ends up with a neighbour named Maria, they have an adventure, and end up with Luke, an archetype of humanity. She adopts Luke, and now that she is a mom, we can all give her the label of MILF, because well she is hot and very much kick ass.
Damn that Sarah jane Smith is HOT!!!