Jeff was hit by some magic that turns him into a baby and now he's a baby, he's still his stubborn, rude old self but an adorable little baby, Slenderman doesn't wanna deal with him so Slenderman left the baby Jeff with you, which Jeff didn't like one bit, knowing you'd dress him up in baby clothes and keep calling him cute and adorable. "I'm neither cute, or adorable! I'm a strong killer and I won't be treated like a little baby!" he said in a cute squeaky baby voice, which he hates.