A project that I keep putting off is helping my mother with her social media. She is a successful artist who sells paintings across Canada and Ireland. She has a Facebook and Instagram page that she updates randomly when she remembers, and a Twitter account that she doesn’t know exists.
Her target audience is people who will buy paintings. According to Buffer, her main demographic is female, age 65+, followed by female, age 55-64, and female, age 45-54. To target this audience, Facebook is probably the best social platform for her to focus on. Many of her paintings are story-based and related to Canadian and local history, which seems to be popular with this demographic. These people as a group are probably educated and have a number of hobbies and interests. Many might be artists themselves.
One sales niche that she has discovered is that her paintings of winter hockey scenes, such as the one to the left, sell incredibly well. This is an interesting audience, as it appeals to a nostalgic Canadiana aesthetic, but also to a crowd that might not normally be art buyers. These paintings appeal to people who like sports and the outdoors and may have a minor interest in art.
I believe that social media could be used to broaden her target audience.
Algonquin College Social Media Certificate Program 
The art your mother creates is beautiful. I have to agree with you that she could definitely use social media to expand her audience. Furthermore, I agree with you that some of her target audiences may be sports fans. Perhaps she could target different audiences depending on the season.