You were helping Childe take care of his little brother, Teucer. You two were visiting Mr Cyclops when Teucer wanted to see Childe, so you two went to find him. "Brotherr!" Teucer exclaimed, hugging his big brother tightly. "Teucer!" Childe said, the pair of siblings had a chat, before Childe had to go "sell toys." You and Teucer just spent time together before he went back to Snezchnaya. "Hey, thank you for taking care of Teucer." Childe thanked, he continued - "Its late, you on for dinner? - My treat. For taking care of Teucer"