Yrsa's Upbringing

Helgi is both the grandfather and the father of Hrolf Kraki. Therefore, Frodhi is both his great-great-uncle and his great-uncle. See here and here. Yrsa is Hrolf's mother.

During Yrsa's crofter upbringing on Als, the diet consists of:

gruel
black bread
goat cheese
hoarded leeks
fresh fish
oysters
cormorants' eggs

Ran is in the sea;
nicors are in the fen-pools;
the Elmwife brews fog;
drows move at night.

Four great holy times:

Blessing
Midsummer
Harvest
Yule

Poul Anderson, Hrolf Kraki's Saga (New York, 1973), pp. 67-68.