“Maternal Instinct” is episode twenty of season three of Stargate SG-1.
Bra’tac arrives at the SGC with the news that Apophis had attacked Chulak. Apophis had survived the destruction of Sokar’s ship by teleporting off it in “The Devil You Know”.
In the episode “Forever in a Day”, Sha’re revealed that her child, the child of two Goa’uld, was a Hartesis child, a human who possessed the entire knowledge of the Goa’uld. Apophis is hunting for him.
SG-1 and SG-2 go to the planet that they think the child is located on. There is a monastery occupied by a monk with some rather unusual powers.
The temple makes mention of ascension to a higher plane, something that the Ancients did, and it looks like this may be the first appearance of an ascended Ancient.