Yup! Actually juts noticed the singing issue this school year. He hates music class! He loved it when it was instruments, now they are singing he hates it! He only goes to music class for 15min. When we are at a bday party and everyone is singing he screams! It is because of..... the different pitches!!!! I learned that when I went to see Temple Grandin! Never did I ever think of it! He is super sensitive to sound, but it never occurred to me that is why he screams when everyone sings happy birthday! ugh! I felt like a big dummy! maybe while se is singing he can play an instrument, drums , guitar, something. They can make it into a game or form their own small band. Maybe this will get him to tolerate it better. They can name their band and make signs for it. I am serious, so don't think I am being sarcastic. My thing is they need to learn to tolerate other peoples hang ups or things they like to do. Everyone cannot modify their lives, life is all about learning to tolerate other people and doing it appropriately. It is not like she is banging a pan in his ear. In order ot be in society and be accecpted socially which is going to have to happen later in life and in school we have to acclimate. Maybe get him some headphones, set a timer and that will be her singing time and explain to her why. He can find another room to go into or put on the headphones, have it on a schedule. I personally think trying to get him involved in her singing might be beneficial, he might have a hidden talent that will shine. My son loves playing the guitar he is 8; we started lessons last year, he doesn't like to practice, but he likes the guitar and he can memorize things easily. Hope this helps have a great weekend!