quote:
No, that was added in. Or more of, extrapolated (or back...polated...whatever). She had mentioned before that she killed off some of her kids that were Robert's via poisoning herself while pregnant so the assumption is that this is just a modified story of that. She killed the kid, but is modifying the story to elicit sympathy from Catelyn.
She also mentions to Ned later that she got off on eating Robert's knuckle children.

