Pinkie pie

Pinkie pie is the laughter of her and her sisters.

Personality
Pinkie Pie is an outgoing, optimistic, cheerful, energetic, happy and hyperactive girl who loves sweets and often speaks and acts in non sequiturs. Loving to make others laugh and put a smile on their faces. She has a fondness of parties and a tendency to throw them on a whim. Pinkie Pie plays many instruments and frequently breaks out into song. She also tends to hop rather than walk, usually accompanied by a springing noise. She is often not taken seriously even by her sisters. She is almost always excited, and manages to keep her excitement after winning thirty-five consecutive games of tic-tac-toe against Rarity while they wait for Fluttershy to catch up.

Pinkie Pie teaches the others to laugh at their fears and helps Twilight Sparkle accept things even if she doesn't understand them. She plays a series of pranks on the residents of Townsville with Rainbow Dash, saying that she loves to have fun. She is very conscientious about this, though: when she pranks someone it's in such a way that no harm is done and the victim gets a laugh from it too. As an example, she once painted all of the apples on Applejack's trees. Applejack was originally furious until she found that the paint was water-soluble. She'll never prank someone if she knows it might hurt them, such as Fluttershy, because of her extreme sensitivity.