How long should you let a child "cry it out"? My neighbours let their 18-month-old scream hysterically, sometimes for way over half an hour, before they go in and calm him down. He is teething and their health visitor says they should let him "cry it out/self soothe". I'm sure this couple is doing their best, but it is very upsetting (not mention disturbing - the walls are thin in a terrace!) hearing him being left to scream for so long. I just wonder if they're getting the best advice. Every parent I have spoken to says they would never leave a child so obviously in distress for so long. (Sorry if this question is in the wrong place or has been answered elsewhere - I'm not a regular!)