The artisan who creates the rubber doll could be the main character in this story. The artisan's creativity and skill are what bring the doll to life in the first place. Their decisions during the making process, like choosing the color and shape, can have a big impact on the doll's 'life' and how it is perceived later on.
Maybe a little girl who owns the rubber doll could be the main character. She is the one who gives the doll a purpose in its life, like taking it everywhere and sharing her secrets with it. So, in a way, her actions and experiences shape the life of the rubber doll.