Kids sleep quality and noise

Hello everyone,I recently argued with another parent about noise around kids. This will sound ridiculous, I promise.While discussing another topic, a relative of mine played a video on a cell phone at max volume about a foot and a half away from a sleeping 9 year olds head. The child did not wake, but I was disturbed and asked her to lower the volume for the child's sake.She claimed that it is "not good" to "tip toe" around kids while sleeping, as to train them to be OK with noise when trying to sleep later in life. I'm in no way a perfect parent, but this seemed rather asinine to me. As someone who is an absolute dragon about my sleep, I want everyone around me to get the best possible sleep imaginable. As far as I've ever known, it is best to sleep in a quiet environment with little to no noise or interruption. At the very least it seemed rather disrespectful to the child. I will change my stance to these issues based on the answers to my questions below. I realize I was projecting my own emotions onto the child, which is why I got so upset - But my questions are these:Should older kids be raised around noise?Does noise affect sleep quality?If noise does affect sleep quality, what kind of issues can arise from noise while sleeping?I've managed to find plenty of articles on adults and babies, but I'm specifically looking for information on older children. (pre-teens?)In addition to this, this particular 9 year old has some intense behavioral issues, and if the lack of good sleep quality could be exacerbating the issues, I would really like to know so i can make a case for reducing the noise around children.Thank you guys for your time and advice. via /r/Parenting https://ift.tt/3we7bZe