I remember once reading a book on calypso (on Google Books) which mentioned that many old-time calypsonians fathered illegitimate children but did not take much responsibility for them. None of the biographies of Invader mention any descendants, so (It is probably safe to assume) it is highly unlikely he had children. True, if he was one of "those" calypsonians with illegitimate children- and most of the singer-songwriters I've heard include at least one reference to their children in their songs- he mightn't mention it.