From established lore, Bear is one of the most powerful healing spirits, so he is your best bet. His children are the only ones who currently have a way of raising the dead. Mind you that way wouldn't work for this scenario but it shows how strong in the healing arts they are.

Deviating from that, you could always go with a new spirit though, something no one has ever seen. The character may never see the spirit directly for a long time. They could only communicate through lesser spirits of the new incarna's brood. They wouldn't know if their benefactor is truely benevolent or maleficent...