In Wolfrider/BoTC he starts growing face-fur during the time he discovers the trolls (uhm, I think Treestump's beard is even fuller, then)
Icetooth's blood was removed, I think ("...Willowgreen's treachery..."), which would enable him to live longer. I guess Windkin is the oldest Wolfrider ever (yes, he's very much Wofrider...).
BTW, how come, that Kahvi is quite old for a tribe, which such a short lifespan. Even if she lived "just" some thousands of years, her tribemates certainly don't!