Thanks for your interest. I hadn't thought what it would do regarding the order because it has already put them in the correct 'birth order'. Since their names are Florence and Albert, in that order I presume it has preferred the first entry i.e. numerical order. As it happened this was the elder, Florence. I have entered the 'twin factor' in the individual texts.
Barry Hughes I am rather pleased I haven't had to deal with sextuplets!