My mom's friend sent a follow request to me on Instagram. Say honestly, should I accept it and follow her back or just leave it as it is?

Yesterday I suddenly saw my mom's friend sent me a follow request on Instagram. She is 46 and I am 22 btw. Actually I kept my Instagram account private because recently my mom too created an Instagram account. Even when my account was not private, my mom's friend used often view my Instagram stories so obviously she will still view it even now too if I follow her back. I am worried that she might tell about some of them to my mom because some of them can be really silly like me curling biceps or headbanging to my favorite rock songs. So should I follow her back and accept it or just leave it as it is?