United Kingdom, May 6 -- Tony Hawk is having the "most fun" ever as a grandfather.

The 56-year-old professional skateboarder became a grandparent for the first time in September last year when his son Riley and wife Frances Bean Cobain - who is the daughter of late Nirvana legend Kurt Cobain - welcomed Riley and has admitted that he is "truly enjoying" this new chapter of his life.

He told E! News: "We are truly enjoying it. We are comfortable with parenting, obviously, but this is the most fun you can have as a parent, because you're just the fun crew!"

Tony - who is also dad to Spencer, 24, and Keegan, 22, with ex-wife Erin Lee as well as Kadence , 15, with ex-wife Lhotse Merriam - added that he takes "no shame" in the great lengths ...