I think Harry Duiven Jr. fought his father instead of Rocky Ven on Friday, 22nd December, 2006 in Berlin. In boxrec.com/results it says Duvien beat Ven
"In what may be a first, Duiven Sr. himself had opened the show two hours before in a fight against own son, 19-year-old prospect Harry Duiven Jr. (6-1, 4 KOs). The unusual matchup came about after the pull-out of Duiven Jr.'s original opponent Rocky Ven (39). Astonishingly the Duivens went at it on full throttle and Junior scored a TKO in round two."
http://www.fightnews.com/hiller34.htm
it's at the bottom of the article (last paragraph)
