I used to think that if a grown up fell down, they wouldn't be able to get up by themselves.
A childhood belief about getting older

others believed things like this
- When I was little I thought grown ups could fly but wouldn't tell me about it or teach me until I got older.— James the Great
- I used to believe that if I fell asleep lying on my front that my boobs wouldn't grow. And they didn't.— Booey
- I used to believe that grown-ups were born "grown up" and that I would stay a little kid forever.— Still A Kid
- I thought grown ups were born grown ups.— mea
- I used to believe that grown-ups were born grown up.— Juleen
- I used to believe that cabbage was lettuce that had grown up.— JHR