This tree has 3 sons named Johannes Otterbach, one born in 1659, one born in 1661, and one born in 1662. It lists the 1659 son marrying Margaret Dornsieffer in 1679. Isn't it more likely that the 1659 Johannes died some time before the 1661 Johannes, and the name was used over again, a not unusual occurrance? 1661 Johannes also died, and 1662 Johannes survived to adulthood. It would then be the 1662 Johannes who married Margaret at the age of 17 years old. The three sons names Johannes mirrors what the 1936 Holtzclaw book says.