I loved April Fools Day as a child. I used to urge my mother to try and fool me, so I could have a chance to catch her at it,, but kind soul, she would not. Then, a bit later, when she was brushing my hair, she announced seriously: "Your hair is turning purple."
The only thing that went through my mind between when she said this and when she said "April Fools!" was sheer terror. The thought of my hair turning purple terrified me. I never thought, "Oh, that must be a prank."
My mom felt so bad. ;-)