Although "On Hallowed Ground" states that Petitioners lose their memories in the Astral Plane, the novels seem to sometimes go in the other direction. In War of the Spider-Queen series Ryld Argith remembers Pharaun when he encounters him on his way to the Demonweb Pits; Gromph accidentally brings a halfling Petitioner named Dietr back with him during his fight with the lichdrow Dyrr. Dietr remembered his family and wanted to see them, which is why he hitched grabbed on to Gromph to follow him back to Faerun.
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