Thank you for your query.
I can understand you concern seeing the myriad problems that your son is having. It is not unusual to have laryngitis
associated with bronchiolitis
which can cause the loss of voice.
I hope your son is receiving antibiotic along with the "breathing treatment". It shall take at least 48 hours or so for the antibiotic to act and we need to be patient.
I hope I have answered your query to your satisfaction.
Wishing your son an early recovery.
Rajiv K Khandelwal