Mor til Ragnhild var Tyrne, datter til kong Klakk-Harald i Jylland; Tyrne var søster til Tyre Danmarksbot, som var gift med Gorm den gamle som rådde for Danevelde den gang.
Halvdan Svartes saga 5

Heimskringla states she is the daughter of Sigurd Hart and of Thorny daughter of Klack Harald King of Jutland, siezed by the bareserk Haki when he had slain her father; marriage with her put off pending the healing of Haki's wounds;but in the meantime she is robbed from Haki by the order of King Halfdan the Black who straightway marries her. i 81.15-83.9 her dream, 83.14=31 her son Harald Hairfair, 85.3=9.

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