The cardinal rule in show business is never to go on after an animal act or kids. Rodney Atkins has a hard time following that mandate, because his son Elijah likes to share the spotlight.

For the past two years Elijah has joined his dad during Music Fest activities in Nashville. In 2007 he went to his dad's fan club party, and last year Rodney brought him out on the main stage at LP Field. This year, the seven-year-old rode with his father in the kick-off parade for Music Fest activities in downtown Nashville.

"I was surprised I was in the picture from the parade, because Elijah was right there beside me," Rodney quipped to The Boot. "Then I took him to the fan club party. He used to not be shy, but now that he's seven he's gotten a little shy but he came up on stage with me anyway."

Rodney says that Elijah had been trying to tell him a knock-knock joke, but he couldn't seem to get the punch line right. So at the fan club party, the singer asked his son if he wanted to say hello to the fans. "Right away he says, 'knock knock,' and the crowd goes, 'who's there?' Elijah immediately says, 'Interrupting cow, interrupting cow mooooo.' And he nailed it. He always upstages me!"

Obviously Rodney misses his family when he's on the road, but this summer is a little different for them. "Elijah and Tammy are coming on the road with me all summer. Usually I'm out doing a show and then get back home as quickly as I can. But now we just stay out there and float around until it's time to go to the next concert."

With this weekend being Father's Day, Rodney is happy to note that he is performing at the Moondance Jammin Country Festival in Walker, Minnesota on Saturday. "We're gonna be up there on the lakes so Elijah and I are gonna get in a little fishing on Father's Day."

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