Stefan had been surprised by the invitation for tea, but his manners wouldn't let him decline. And, if he was being honest, there was probably some idle curiosity at work as well, as well as a sense of duty. Though Damon was the Head Vampire, as Damon's brother, Stefan was also his brother's representative, unofficially if not officially, and since Tabi and her grandmother were still relatively new to Crescent Hills, this could be seen as a 'welcome' visit from the most powerful vampire family in town.
Thus, representing the Salvatores, he arrived promptly at four, well-dressed in a charcoal grey suit, armed with a small bouquet of iris, and rang the bell.