"Sometimes," Big Mac's wife said, "I really think you love that doll more than you love me."

In a moment of foolishness, not long after Twilight Sparkle first moved to Ponyville, the unicorn cast an enchantment upon an old doll of hers. Later that same day, the unicorn's teacher dispelled the malign glamour. Surely, not even traces of the spell remained.

Or so one likes to think.