03/12/2013 02:50 pm ET Updated Mar 13, 2013

'Parenthood': Craig T. Nelson Blasts NBC's Treatment Of The Show

On "Parenthood," Craig T. Nelson plays the Braverman patriarch and the actor is defending his clan and the show against its network NBC.

"There are all these people responding to our show and NBC is completely out of it," Nelson told ET. "They don't promo the show, you don't see anything about it out there. It's like this hidden gem, but why are they ashamed of it?"

"Parenthood," the perennial bubble show, hasn't been a ratings hit -- though its numbers did grow in its most recent fourth season. But the show has earned very devout fans, who, year-after-year worry their favorite series will come to end.

"We should be doing more episodes. Full seasons," Nelson added to ET. "I don't understand whatever the agenda is behind the scenes. It's very confusing. Having been around as long as I have and been on a couple of shows -- one of which I ran -- it doesn't make sense to me."

Thanks to the higher ratings and the new-found energy behind the show (largely due to a cancer storyline that carried most of Season 4), a Season 5 seems likely. Though nothing is definite, "Parenthood" creator Jason Katims seemed to be hopeful that NBC would be kind enough to renew the show.

"It sometimes happens where you can feel that people not only think the show is a good show for the network, but they themselves become fans of the show," Katims told TV Guide. "Also the show has started to do better and is -- while it remains and I'm sure always will be on some level -- a bubble show, the show's audience is solid and even showing signs of growth so I think that doesn't hurt."

For more on "Parenthood," click over to ET Online.