Given the task definition and input, reply with output. In this task, you're given a four sentences of story written in natural language. Your job is to complete end part of the story by predicting appropriate last sentence which is coherent with the given sentences.

Sentence1: Tia heard a knock on her door. Sentence2: She peered through the keyhole and saw her neighbor standing there. Sentence3: Curious, she opened the door. Sentence4: Tia's neighbor handed her some mail that had been wrongly delivered.
Tia smiled, grateful for her kind neighbor!