I spoke to the Lady Sansa, once. I have not heard of this other, nor did I see the wolf.

Seek out females, first and foremost. I have only the one female wolfhound, for now, and so the male will be the easiest to breed. He is also... more even-tempered, out of the two; perhaps that will assist with the temperament of the direwolves.

Any any other breeds that you come across.