In the Scottish fishing villages it was common to marry relatives. I had a great-uncle who was married 3 times, and all his wives were related to him, the 2nd and 3rd ones being sisters (and his 2nd cousins). I was told that when his 2nd wife, Annie, died, her sister Lizzie came along from the next village to keep house for him, but of course tongues started wagging, and one day Annie and Lizzie's old mother came to the house and said, 'John, wad ye no' tak Lizzie tae wife?', which he duly did.
I know of another fisherman in the same village who was married twice, and his wives weren't related, but they were both called Janet Brown. I suppose it saved him having to memorise another name.
Harry