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1.
Interchangeable with the term "Irish Twins," Vatican Twins are two siblings who were born less than 12 months apart. Derived from the perception that Irish Catholics, due to their opposition to birth control, would have many children in short periods of time.
My parents got drunk a lot in the 80s and that's how come my sister and I are Vatican Twins.
by evvfrenchie April 14, 2009