MOB RULES!

De Niro prenup a deal Tiffany can't refuse

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Tiffany Chen has been pushing for marriage with twice-divorced Robert De Niro since Gia was born, sources say

TIGHTFISTED tough guy Robert De Niro's baby mama Tiffany Chen is pressuring the Raging Bull star to put a ring on it, but the 81-year-old cheapskate won't dive in to marriage again without the protection of a prenup, sources tell GLOBE.

Snitches say the Oscar-winning miser resents every penny he's had to shell out over the years to his two ex-wives and to the former assistant who sued him, so he's desperate to avoid putting any more of his $500 million fortune at stake.