"Children are  natural musicians, as they readily sing, dance and play music from the time they are infants. People ask me all the time how they can tell if their child has musical talent. I assure them that their child – indeed every child – has musical ability that can be developed into a satisfying and lifelong relationship with music.  However, as they get older, some children begin to get messages from peers, family members....."

This is a beautifully rendered video that includes some leading authorities on the impact of emotion and trauma on the singing and speaking voice. 

"​Californian scientists have identified the source of the sigh. It is not just a response to sadness, depression or despair: it is, also, they report, a life-sustaining reflex that helps preserve lung function.."

This article  and research by Alexandros N. Constansis is interesting mostly because the author is a voice teacher and also going through a hormonal injection process.   It offers a helpful window into the process of voice change, and what occurs during the adult FTM physical transformation.