It's not Lindsay Lohan topping up her dad Michael Lohan 's prison commissary account – the mystery bankroll turns out to be courtesy of his estranged wife, Kate Major , RadarOnline.com can reveal.

"Everybody assumed Lindsay was slipping him money out of guilt or family loyalty," a well-placed insider explained. "But Lindsay has completely cut herself off from Michael's chaos." Tap Here To Add Radar Online as A Trusted Source Article continues below advertisement

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Michael, 65, is serving time in a Florida correctional facility after yet another run-in with the law.

But while his relationship with Lindsay remains lousy – sources said father and daughter "barel

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