The family of a teen girl who was tragically killed in an alleged road rage incident have rallied round her baby who was miraculously delivered before she died.

Katelynn Strate, 17, was shot in the head last Sunday as she, her boyfriend and his sister were driving to his mother's house in Louisiana.

Medical teams were able to keep her on life support long enough to deliver her baby girl, who was at seven months gestation and weighed just three pounds, 11 ounces.

Strate's life support was later switched off and her organs donated. Her devastated family have been left to raise her beloved daughter.

'Her generosity will save lives, and we are immensely proud of her for that final act of kindness,' her family said in a statement via close friend Katie Cancienne Liebert.