Hello, I am a Brouwer, descended from the Jellema family through my grandpa, who was born in Dokkum, Friesland. my family lives in Canada now, but among our Dutch-Canadian community, my family is part of the group lovingly referred to as "The Dark Dutchies" most of us have dark eyes, black or dark brown hair, and easily tanned skin. my dad is 192cm tall, and my tallest cousin is around 2m(which is more or less the scolar agreed heigh of Grutte Pier now). my dad has done the Ancestry DNA test and both his parents are around 98% northwestern Germanic. the rest is Danish or Norwegian, so no chance of French, Spanish, or Mediterranean DNA mixed in there as we thought previously.
The interesting thing was originally the test said we were only 19% Dutch, and the rest was mostly British. then we got an email from ancestry that said Dad's DNA was almost an exact match to the people in southeast England that are descendants of the original Angles, Saxons and Jutes that came from Denmark, Germany, and Friesland. So my guess is the original tribes that lived in those areas after the Romans wiped out the original Frisii tribe were part of the anglo-saxon invasion, but some obviously stayed behind, and that's who the Jellema's and Donia's are descended from.
I've made it up my Jellema tree back to Jarichs Jelsckama born in 1290, his grandson had 4 children, one was Wybe, who's great grandson married Zus Gerlof Donia and was the father of Wijerd, and another was Tiabeco, who is my 21 times great grandfather. So I'm not a descendant of Pier or Wijerd, but the latter and I share the same ancestors.