Originally Posted by Anti Hero
I'm not suggesting they leave White Harbor, just annex the lands and the fortress of the Dreadfort.
They might get a part of some lands. In ACOK we see Wyman taking Hornwood, although he proclaims he just defends it from the Bastard. He seems to be pretty sincere in helping Starks just because of "the promise", so I am not sure what would he want.
He may also die pretty soon and we don't know much about what would his son do.
Some cadet branch may be set up there (although I am not sure there is any Manderly left for that, they do not seem to be a big family and Wyman's second son is dead).
The concern would of course be that they would be getting little too powerful with this and that could cause problems in the future.