I agree she doesn't have to tell you ..... So I would say she is either not telling you because she is either not taking her child out and therefore no change needs to be made or she is keeping her child home with her during mat leave and she's afraid you will fill her spot now and give her notice .... So if you only ask for two weeks written notice to end care then that's all she's required to give you. But if it bothers you that much then say "Susie says she's going to be a big sister congrats ". Then its out in the open. Then you could say are you keeping Susie in care while you are on leave or should I start advertising for fall? There's nothing wrong with that and then you would have your answer. Then I would advertise anyway just in case