This particular couple seem to have been particularly fertile; each time I brought then together to try for a baby they obliged (three times over on the last occasion). I can't remember any couples producing babies on the first try each time; usually at least two, generally more, attempts are unsuccessful. With several families I have to resort to Baby Boost after a series of failed attempts, and they don't always produce as many kids as I'd like; that is, the maximum of six!