For sure there is more info on Gustaaf.. Not in the book, but there are some nice people in Hoogeveen, that pointed me to genealogical information from that region. Indeed, Gustaaf, his wife and probably 8 children emigrated to the USA in 1910. Round about 1912, his wife Johanna Christina Exel died. Gustaaf remarried to Harriet (I don't know her last name), and there were probably 3 more children. Dorothy is the eldest of the 3, I think, born in 1930.