Grandpa's Goodbye

My mom told me that when I was just a small child, my dad have this Japanese friend who brought us toys from Japan. One of them is a battery operated toy where small cars will be carried up by an escalator and upon reaching the top, it would cruise down to the same place where it started and perform the same action over again. One night, the toy started to run by itself though no one's touching it. She finds it very strange and went ahead to check it out. To her surprise,  it doesn't even have batteries in it. She began to have trouble sleeping and choose to wait for my dad to return from work. She told him what happened, but even my dad can't figure it out. 

The following day, they received a letter asking them to go to the province because my mom's dad passed away. They surmise it was my grandfather paying a final visit to her eldest daughter, my mom.