Could a reason why Ned Stark never fostered out Jon Snow which is more the norm for Northern bastards (i.e. Larence Snow at Deepwood Motte) is that part of Lyanna Stark’s promise to keep Jon Snow at Winterfell while he grows up under his protect? I guess I’ve wondered how much of the cover story for Jon Snow (that he’s Ned’s bastard and he’s raised at Winterfell despite Catelyn’s displeasure) was Lyanna’s idea or was Lyanna’s promise just sorta basic & vague and Ned came up with the rest of it.