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So based on genetics and in-game lore, it seems like Rosalina's parents MAY be Peach and Mario. But Rosalina's mother is dead, and Peach doesn't seem to be. Not to mention Rosalina and Peach look to be the exact same age. So what's the deal? Are they actually related? The answer is YES. Super Mario Galaxy explains how...even if it is a little difficult to decipher.