Hugh Hefner always had his wife's best interest at hand with a crib and a boat load of money. (Gallery)

As quickly as Hugh Hefner said "I Do," he rolled out a plan to make sure his wife would be provided for when he dies ... a plan that included a sick pad and Millions of dollars..

Sources obtained the deed to a Hollywood Hills home that is held in trust ... a trust controlled by Crystal Harris. Hef bought the 5,900 square foot house for her back in 2013.

And get this ... sources familiar with Hef's estate plan tell us he also left Crystal $5 million. Based on what we know, the deal is part of a prenup Hef and Crystal signed before they got hitched in 2012.

As for the house ... it's got 4 bedrooms, 5 baths, terraces galore, walnut floors, floating staircase, a theater, an "over sized game and entertainment area," an infinity pool and spa, and smart technology.

I think she should be as comfortable as she wants to be once she settles in and allow Hugh's life and death to be of joy and not grief. Hugh died at 91.