Kind(eren):
According to a family tradition in the family "de Bruin", they are descended in the male line directly from a bastard son of Maarten van Rossum. The tradition could, however, merely have been wishful thinking. Not everyone took it seriously. (My source is my wife Sophia Arnolda Gill-Hoffstädt, who heard stories from her mother Arike Hoffstädt - van Egmond and her aunts To and Mies (both born van Egmond, first names, I'm guessing right now, Catherine and Wilhelmina)
I'm guessing that this bastard son would have been called Gijsbert, who would be the father of Willem Gijsberts de Bruijn (born before 1578, died approx 1612). That's the simplest way to make a bridge between known and unknown ancestors which fits nicely to the dates we have.
The male de Bruin line, going into the past, stops dead with Willem Gijsberts de Bruijn. So we can ask: who was Willem Gijsberts' father? Gijsbert? Gijsbert who? And who kindly supplied the surname "de Bruijn"? Apparently, a recent de Bruin, M.G. de Bruin, former director of Dutch Railways, had a family shield made with the van Rossum contribution in it, with the heraldically correct way of indicating an illegitimate heir. I can find no record of that.
Richard Gill (husband of Sophia Arnolda Gill-Hoffstädt), Apeldoorn, 19 August 2019.
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