My mother cried over a baby sock while packing my room

Dear Delyara, I am thirteen and we are moving house. I came into my room today and found Mum sitting on the floor holding a tiny blue sock. Mine from when I was a baby. I started laughing because it could fit over two fingers. Mum was crying. I asked what was wrong. She said nothing, just “You used to be this small.” I said obviously I am not anymore. That made her laugh and cry at the same time, which was embarrassing. We are only moving twenty minutes away, so I do not understand why every box makes her emotional. Dad died when I was eight, and this is the house we lived in with him. Maybe that is part of it. I told Mum she could keep the sock. She said it belongs to me. What am I supposed to do with one baby sock? I put it in my backpack because throwing it into a moving box seemed to upset her. Tonight, I looked at it again. I do not remember ever being small enough to wear it. Mum does. I think that is something parents carry that children cannot: whole versions of us that are completely gone from our own memory but still alive enough to make them cry on a bedroom floor.