Now that Matt Bellamy and Kate Hudson have welcomed son Bingham into the world, Mr. Bellamy wants to make sure his bond with Kate's son Ryder is strong.

Ryder, the son Kate had with ex-husband Chris Robinson, had a blast playing in the Malibu sand with his soon-to-be stepdad. Water guns are a blast ... literally!

What a great way to give new mom Kate some much needed rest. With all of those late-night feedings, we bet she needs it.

Check out Kate's boy riding a sand dune ... after the jump.