hi dear, by 11 months baby should be sleeping throughout the night, maybe only wake up once or twice for a feed and immediately go to sleep. does she sleep during day time? do not let her sleep after 5 pm in evening, and establish a bed time routine, like bath, reading book, sleeping. do not let her get over stimulated or over tired before bed time. ensure she has a full stomach before sleeping. also ensure she is not too hot, too cold or feeling wet during sleep..