amelioration: change in meaning to something more favorable
The original word "nice" meaning "foolish" has a bit of a negative connotation. A person described as foolish is often thought to have done something childish without a lot of forethought. The foolish behavior often results in some type of accident or harm. Now "nice" means to be kind to or thoughtful of others. People are nice when they give compliments, hold the door for someone, or help out. The meaning of nice in how it is used now from the way it used to be used is more favorable.
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.
