Hamingja

The hamingja was a kind of female guardian angel in Norse mythology. It was believed that she accompanied a person and decided their luck and happiness. Consequently, the name was also used to indicate happiness, and that is what it means in modern Icelandic. When a person died, the hamingja passed to a beloved family member and thus accompanied a family for several generations, continuing to influence their fortunes. It was even possible to lend one's own hamingja to a friend, as happened when Hjalti Skeggiason was about to leave on a perilous voyage and asked King Olaf II the saint to lend him his hamingja.
It usually appears during sleep in the form of an animal, but it can also be the spirit of a sleeping person who appears in the form of an animal, as Bödvar Bjarki in the saga of Hrólfr Kraki.
In Norse mythology, "hamingja" (Old Norse "luck") refers to two concepts: 
Both Andy Orchard and Rudolf Simek note parallels between the concept of the hamingja and the fylgja. Luck may be transferred to a descendant of the owner, or to a member of a tribe for a perilous journey, it accords wealth, success and power, and it accrues over a life time. Sometimes hamingja is used to denote honor.