Yes I know we don't have a crystal ball, but the Queen had 4, incl Edward when she was 40. IME families often repeat the number of children-all my friends who have 3 DCs are one of 3 themselves. So Catherine may be happy with 3, but she does seem quite a broody type so I wonder if there may be one more? Obviously money is not an issue and she appears to spring back into shape, other than having horrible morning sickness.