Tathagata - Book One: Birth
The Buddha had not intended to return so soon. But things were not well with Earth, and the worsening (by the day it seemed) situation could not brook another 2,500 years of idly standing by. That much was clear.
So after a brief reconnaissance life as Giordano Bruno, he returned in current times to again set things right. This time as a young girl called Ruth Marten, Melissa's daughter.