[TOMT] [BOOK FOR PRETEENS] [MID 2000S]

Struggling to remember the name of a series I loved when i was younger.

The series revolved around a teenage girl being hit by a car on her 13th (?) birthday, then going to heaven to train as a guardian angel. She would be assigned random children throughout different time periods who would soon undergo a family tragedy of some kind, and her job was basically to help them and provide comfort. For example, she was sent back in time to help a girl from the 1920s whose dad had just died in a car accident. I believe her name was Tracy or something, but I'm most likely wrong on that. She also had a best friend in heaven who worked in heaven's nursery, and they would spend a lot of time on the beach together. She might have also had a love interest, but again I could be wrong.

If anyone knows what I'm talking about, please let me know, thanks :)