The best advice I can give is to get your baby into a routine that fits around your other children to ensure that you are able to spend quality time with them, otherwise they may grow to resent the baby and this is where the problems start. Your children’s behaviour may become erratic temporarily following the birth of your baby, however this usually settles in time if you deal with it patiently and with understanding. In some cases reward chats may help. If you are at all concerned speak to your health visitor but keep reminding yourself that it is most likely a phase while your child adjusts to having to share your attention and just generally the idea of having a new sibling.