https://yle.fi/uutiset/3-10768853

Father of Finnish 19th century writer Aleksis Kivi was long rumored to be illegimate son of nobleman Carl Henrik Adlercreutz. To test if this was true gene tests were done to descendants of Kivi and members of Adlercreutz family.

Results show that Kivi was not descendant of Adlercreutz. Kivi belonged to haplogroup I1. Adlercreutz family was shown to be member of the N1c1 clan
https://en.wikipedia.org/wiki/Adlercreutz