Let's go back to 1973

Roxanne Weasley (known as the daughter of George and Angelina Weasley) is fascinated by the marauders era and would love to go back.
Roxanne is going back to hogwarts for her 3rd year but when she runs through the barrier she is in 1973. Someone has sent her back in time to the year of the marauders, but there must be a reason why, she might be able to save those who died including James and Lily Potter.