Rich Jackson is the uncle and adoptive father of Sally Jackson.
He took in his niece after his brother, Jim, and sister-in-law, Estelle, died. During Sally's last year of high school, Rich was diagnosed with cancer, his asked Sally to drop out to tend to him due to his health insurance running out. He died, leaving Sally to have to work small jobs because she dropped out of high school to take care of him.
Percy mentions Rich when he arrived home from being expelled from Yancy Academy earlier in the school year.
According to The Lightning Thief, Rich was a caring man who greatly cared for Sally.