I have a ds whose bedroom is above dd - a year apart in age.When DS starts to masturbate im sure dd will hear and ive not clue what to do as i think it will annoy! a freind of mine some time ago had similar issue and it really annoyed her other child- she said to be quiet - recognising right to do it,but it did not always work !! im quite shy and i dont know how id deal with this.My childresn are quite argumentative at mo and i can anticipate trouble so- whilst there is not script to this or many parent stuff- id really appriciate others experince and advice!i wd say to my other child of course that its normal etc !! its just handling the sit!!