1984 What happened on the day that turned out to be the last time Winston saw his mother?

Winston remembers that shortly after his father disappeared, he lived with his mother and his baby sister. Times were difficult, air raids were common, and rations were small. Winston's mother was highly distraught. She performed all her household duties, but rarely spoke, and sometimes held Winston for inexplicably long periods of time. Winston was a selfish young boy who always demanded more food from his mother even though there was barely enough for them to share, and sometimes even stole from his little sister's plate. One day, Winston's mother broke apart the two-ounce chocolate ration, giving three quarters to Winston and one quarter to his little sister. Winston snatched his sister's piece and ran from the house, his mother screaming for him to come back. He never saw her again. When he returned to the apartment several hours later, his mother and sister were gone.