Who is Peter Van Wagener from Narrative of Sojourner Truth and what is their importance?

Sojourner Truth's son, Peter van Wagener, faced life as a slave before Sojourner was able to go to court and save him. He lived in New York City with his mother for a short period of time before falling in with a bad crowd. Sojourner found help for son and secured him a position on a ship instead of time in a jail cell. She never saw Peter again, but she did receive a few letters.