While researching my ancestors' lines at MedLands I came across an interesting information. It says that the fife of Heinrich Borwin II's wife, Christina of Sweden is, in fact, illegitimate daughter of William "The Lion", King of Scots and his mistress.
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12. CHRISTINE (-after 20 May 1248). Her parentage and marriage has been researched by Andrew MacEwen[604]. “Nicolaus princeps Sclauie” confirmed that “bone memorie dominus Henricus de Werle pater meus” had donated property to Kloster Amelungsborn, for the souls of “sue et matris mee dominie Christine necnon pie memorie domini Burwini aui mei et patrui mei Nicolai”, by charter dated to [1232][605]. Pope Innocent IV permitted “nobili mulieri --- Sorori...Regis Scotie” to enter Doberan monastery, founded by “nobilis vir B. de Rozstoc maritus tuus”, to pray, dated 20 May 1248[606]. m HEINRICH BORWIN [II] von Mecklenburg, son of HEINRICH BORWIN [I] Herr von Mecklenburg & his [first] wife Mathilde von Sachsen (-5 Jun 1226, bur Doberan).
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The main source provided is MacEwen, A. B. W. ‘A Far-Fetched Alliance: the Marriage of Borwin of Rostock and Cristina of Scotland, Foundations, Vol. 7 (June 2015), pp. 3-24.
It truly does strike me as a far-fetched conclusions and I just don't see it being true, but... who knows? Did anyone research that line or encounter MacEwen's article on said topic? What does it say?