A strict mother could have impact on her son as well as challenge and influence those around her. I admit it’s not as easy to encapsulate into a short phrase, but I thought it sounded right.
I meant more if it’s supposed to be in the same context. If the main character is the single mom, and the relationship is between mother and son, then the influence character is probably not going to be a strict mother, right? Unless the influence of the son makes the mother strict or something.