While she was not originally one of the available bachelorettes in the Japanese version of the game, she became one later with a free update. In English, she becomes a bachelorette via "The New Neighbor" DLC.
Stephanie will reside in Westown after she has become available to interact with. She will not participate in any Festivals except for Flower Festival and Winter Thanksgiving Festival.
You can have a child with Stephanie and you can get all family events with her, but she doesn't have a spouse exclusive event (that is usually required to be seen before you can get the pregnancy scene) and you can't have meals with her either.
Cheese Fondue (Cheese + Broccoli + Carrot + Potato + Pumpkin. Recipe is for sale at Garden Grill once Westown is Town Link Rank A, or after you have cooked 7000 dishes in your kitchen)
Grape Wine, Cheese +, Red Cloth +, Black Cloth +, Red Alpaca Cloth +, Black Alpaca Cloth +, Red Rabbit Cloth +, Black Rabbit Cloth +, Red Suffolk Cloth +, Black Suffolk Cloth +, Red Llama Cloth +, Black Llama Cloth +
Tree fruit, Pumpkin, Tomato, Onion, Corn, Sweet Potato, honey, Wasabi, Spinach, Soybean, Maple Branch, Cherry Tree Branch, Coral, green fabrics, blue fabrics, white fabrics, yellow fabrics, silver fabrics, gold fabrics, cheese, wine (except Grape Wine), Pumpkin Salad, Tomato Salad, Soybean Salad, Baked Cheese, Baked Sweet Potato