So just to make sure he really is his great*8 grandpa:
All I did was follow the lines of his sire and dam, and Man O War pops up as the greatgreatgreat grandsire of Sam's greatgreatgreat grandsire, Lucky Straw. Sam is Docs Luckylynx Chance.
I know it's a ridiculous question, but the more I think about it the more my brain mushes. :p