AceShowbiz - Justin Timberlake had a rude awakening early on Monday, April 30 when his young son sat on his bare back with a soaking diaper as he slept off a late night. The "Cry Me a River" hitmaker and his wife Jessica Biel are currently potty training three-year-old Silas, and all is well during the day, but the youngster wears a diaper to bed.

And on Monday, as exhausted Justin tried to sleep off a late night after a performance in Los Angeles, Silas decided to wake dad with a pee-filed surprise. Appearing on the "The Ellen DeGeneres Show" on Tuesday, May 1 in a pre-taped segment that was recorded shortly after he and his former *NSYNC bandmates had unveiled a star on the Hollywood Walk of Fame, Justin recalled his soaking start to the week.

"He's a big boy now, which he will be happy to tell you," Timberlake shared. "We're getting really well down the line with the pee-peeing on the potty thing, but at nighttime we give him a diaper. And so I feel the hand and he comes in and he hugs me, and right on my back I'm like, 'That's really wet'".

But the unpleasant moment is all part of being a parent for Timberlake. He joked, "Anybody who's a parent out there knows that it’s like - you've never been more excited to be peed on".

During the show, Justin surprised Ellen DeGeneres's studio audience by bringing out his former *NSYNC bandmates and playing a game of Never Have I Ever, during which the "SexyBack" hitmaker confessed to making out with a member of the Spice Girls.