Rod Stewart may be thrilled to become a grandfather at 66, but a friend of the gravel-voiced icon reveals that doesn't mean he isn't furious at daddy-to-be Benicio Del Toro for casually getting his daughter pregnant.

The 44-year-old Oscar winner announced through a rep this week that he is the father of 31-year-old Kimberly's baby, despite not even being a couple. I'm told that even though Rod has had eight kids with six different women, he had hoped Kim would walk down the aisle before having a baby.