skallagrim and MacMillian/Mullen relationship

In researching information which I figured was merely a matter of time before it was removed due to unreliability, anyhow, I was looking to see if today might be the day I uncovered more about who Sarah Jane Humphrey McMillian was and instead I found a very interesting read that suggested the surname MacMillan son of Millan could be Celtic for "Mhaoilavin" or bald one and it was immediately interesting to me that Skallagrimson is also similarly translated. And it is funny to me that my mother's side of the family are bald, though she isn't... but, it is her family that comes from both Scotland and Iceland, while my father is German/Swedish so I always tried to trace my Icelandic heritage through his Scandinavian side (it makes reasonable sense and sorta works) but perhaps only to me, the likeness of the surnames provides more support to the idea that my mother is only deceptively Scottish but lent me more of what I consider my Norwegian heritage, not my vikingish dad with his Scandinavian teachings.

Lastly, it was also my assumption that the McMullens were all originally from Ireland, and the McMillans just got separated and started talking differently... it is like how I found Anderson ancestors in a census record as Hendersons and a woman born as an Erickson was listed in a census record as Margaret Cerricks. I think no matter how well-meaning those record takers were "or the indexers" a little leeway must be granted for spellings of names...like Babcock and Badcocke. 

As I was reading this one more time, my toes aren't shriveled up in the bath yet". I wanted to share a cool story about Surnames. I had been trying really hard to find out more about this chick from Sweden/Gotaland.  And at the time I was in a conversation with a woman with the same surname. And long story short, she told me that her husband's family was outlawed to America and so they just picked a name out of a hat (like the Durbevilles from the movie "Tess") so, she wasn't even related by marriage though she had the right surname. Interesting, huh? Makes you wonder how much of written Geneaologies are made up for one reason or another and might not match at all with our DNA.