Grandpa, I think that when you put your mind in this body’s young brain it did what young brains do: it shoved the bad thoughts into the back, and put a wall around them. But those bad thoughts are the real Rick. The fact that you’re old, the fact that we’re all going to die one day, the fact that the universe is so big nothing in it matters, those facts are who you are! You’re trapped in there, and you can only come out in the form of Tiny Rick’s teen angst!

Summer Smith, Rick and Morty