According to some researchers, cognitive development continues beyond Piaget's formal operational stage to the level.

my hamster died and my second hamster i got after that one died as well. i also lost two birds named rainbow and kiwi, (they didn't die, they flew off and escaped). i lost a cat named omi, and a dog named snoopie. the best way i got over it is, paying my respects, and just thinking that they were in a happy place. as well as just remembering but not thinking about it all the time, just do fun activities and try not to think about it too much. hope you feel better. i'm sorry about your loss. : (

alzheimer's disease is a brain disease where you forget things that happened moments, even seconds before hand. reward me plz