There are numerous wolves in Norse mythology.
First, we have Geri and Freki, accompanying god Odin.
Fenrir is a monstrous giant wolf, son of the demoniac god Loki and a giantess, Angerboda. In both the Poetic Edda and Prose Edda, Fenrir is a son of Loki and is foretold to kill the god Odin during the events of Ragnarök, but will in turn be killed by Odin’s son Víðarr. He is attested in the Poetic Edda, compiled in the 13th century from earlier traditional sources, and the Prose Edda and Heimskringla, written in the 13th century by Snorri Sturluson.
Skalli/Sköll and Hati Hróðvitnisson, sons of Fenrir are responsible for chasing the sun and moon across the heavens, and finally devouring them at Ragnarök when the world comes to an end (in another source, it is the wolf Fenrir).
Sigmund and Sinfjötli
In Norse mythology, Sigmund and Sinfjötli are a father and son who are featured in The Saga of the Volsungs.
Sigmund is the eldest son of Volsung (King of Hunland) and Hljod (daughter of giant Hrimnir). Sinfjötli is the son of Sigmund and Signy. Signy is the sister of Sigmund and slept with him in the form of another woman. Sigmund and Sinfjötli would often go into the forest would to kill men and steal from them. During one of these trips they came upon two sleeping men who were wearing gold rings and had with them two wolf skins. The wolf skins had a spell on them that forced the wearer to wear the skin for 10 days at a time. They put on the wolf skins and were unable to get them off, they went their seperate ways and only agreed to call for help from the other if they ran into at most 7 men. Sigmund came across 7 men and called out to Sinfjötli who came to his aid and killed them all. Soon after they departed again, Sinfjötli came as across 11 men, fought them, and killed them all without asking for help from Sigmund. Sigmund became angry at him for not asking for help and bit him in the windpipe. Sigmund then carried Sinfjötli back to the hut and sat by him.
One day Sigmund saw 2 weasels and watched as one bit the other in the windpipe, ran off, and returned later with a leaf. The weasel set the leaf down next to the other who was suddenly healed. Sigmund went out and saw that there was a raven flying with a leaf, who brought it to him. Sigmund took the leaf and put it over Sinfjötli’s wound, healing him. After the 10 days ended they took the wolf skins and burned them so that they could do no more harm.