Not much is known about Owltooth's history before meeting the party. It can be surmised she lived a relatively normal life for a winter wolf, hunting to feed herself and her daughters and raising her daughters to learn these skills for themselves.
Eventually, presumably while Owltooth was either not present or too distant to stop them, Owltooth's daughters Lostrock and Cloudywind accidentally crossed the border into the territory of some ice mephits while hunting. The mephits took exception to this, and attacked the winter wolves partially in retribution and partially out of boredom. Owltooth led her daughters in running from the mephits, but all of them got significantly scratched up before they happened upon the party.
Cree immediately figured something was fishy, and began asking the mephits pointed questions. Anther, on the other hand, didn't see the conflict as being any of the party's business, which prompted an incensed Owltooth to ask her if she was as stupid as the mephits, or as lacking in compassion. Unfortunately for Anther, the rest of the party wasn't willing to let the situation sit, and too stupid to be intimidated the mephits eventually decided to pick a fight. Owltooth and her daughters helped the party with the consequent battle against the mephits (and the ice elemental they summoned to help).
Eventually the enemies were defeated, and a grateful Owltooth introduced herself and her daughters to the party. After learning the party was trying to track down the thorn monster, but had lost it in the blizzard the night before, Owltooth, Lostrock, and Cloudywind started a howling chain with neighboring packs of winter wolves to try and track the monster for the party. Upon learning it had gone to far to catch, Owltooth then offered to guide the party to a nearby herd of hippogriffs. She introduced them to the 'griffs, translating between them and the party. Once the party had secured the help of the hippogriffs, Owltooth offered to watch over Dahlia's dog Marigold, who could not ride.
Much later on, after the party had retrieved the thorn, Cree and Dahlia returned to the hippogriff heard to pick up Marigold, meeting up with Owltooth one last time. She seemed pleased that they found what they were looking for, and remarked that Marigold hadn't been any trouble (with a lowkey implication that Cloudywind hadn't been so well behaved). Cree and Dahlia thanked Owltooth again for her help, which she graciously accepted, thanking them in turn for their help with the mephits and for ridding the Frostfell of the monster.
Owltooth has a fairly serious, no-nonsense air about her. She isn't unkind, but she isn't effusively friendly either, preferring to carry herself with quiet dignity that stands in stark contrast to her daughter Cloudywind.