My mother's family is the same. She has four cousins, of her own generation alone, with the same first name. My grandfather's name is Jan. As a result, I have a cousin called Jan, a cousin also called Jan but referred to as Little Jan to distinguish him from the other one, a cousin called Jan-Pieter, and a second cousin called Jan-Jurjen (who is the child of cousin Albert, and named Jan-Jurjen after Albert's brother Jan and Albert's father Jurjen). No one's ever tried to do a family tree, it's a genealogist's nightmare. I was the first child in the family not to receive a family name. There was apparently some kerfluffle. They have, however, since gotten over it, and I have many younger cousins and second cousins without family names now - once my parents dared to do it, it was apparently ok for everyone else too.