context: Yesterday I boiled milk for my mom. Whenever she goes to work she asks me to do tasks for her so that when she comes home she doesn't have to do it. Yesterday she wanted me to walk across the street to the store and buy some milk. I did, and after that I walked back home and closed the door. My mom left me instructions how to boil the milk for her. I got a big pan and put it on the oven. I turned on the oven and made the pan hot by turning the dial to high. Once the pot was hot enough I poured the milk inside, I poured around half of it. After a while the milk started to get hot, which I could see because it would move and I saw steam. When bubbles started appearing in the milk, I knew it was boiled and done.
question: When did they buy the milk?
reference: The same day.
candidate: milk dispenser