have twins, one is inclined to wake the other if they chirp during the night! of course its better for them to get used to the noise, but been there and bought the t shirt and it ain't happening. one baby is a very light sleeper. also the white noise blocks out street noise like kids playing etc and i find it works a treat. 12 hours solid sleep. i've been using the lap top in the room on a temporary basis but as its working i'll just get a little cd player.