`  == Motivation for a few of my changes ==  I removed the wording ``early 19th century historians`` as the impression I get is most later historians has accepted their view and decided that the matter has been laid to rest. For example, Dick Harrison, in Jarlens sekel discusses the family of Birger jarl, but does not even mention the fact that Ingrid Ylva could have had royal blood. He does mention Sune Sik as a donor to Vreta Abbey though, but in a completely unrelated chapter. He also makes it clear that the donation was signed in 1297, so I removed ``recorded``, which made it sound like it could have been made earlier.  Also, I'd prefer if this article was moved to just ``Sune Sik``, which seems to be the most common in Swedish history writing and doesn't suggest that Sune was actually the son of Sverker.    `