The word 'mother' should be capitalised in place of someone's name. However, since you have already mentioned that she is called 'Sonya', the word 'mother' should not be capitalised.
He would benefit from seeing a live performance because he could then see experienced actors play out the emotions, therefore giving him a more in-depth look on the feelings. This would make his essay much more fleshed out and analytical.
We cannot rely on only our five senses we have to use scientific tools to understand what is beyond our senses. Only using our five senses in inadequate.
