We have such a constant turnover in this business that I tend to make ammendments but for new people coming in so old people stay on old contract they signed. If they go on mat leave and child stays full time during mat leave the old contract stays in place AND the new child coming in if they start gets to stay on old contract too including lower daily rate (this is my version of a sibling discout). If child stays part time they stay on old contract but new sibling is charged new rate when they start. If child is pulled during mat leave and then both want to come back they both come back on the new contract.