Call it the linebacker lineage, an ongoing mentorship program in the heart of the 49ers' defense.

Just as Takeo Spikes guided Patrick Willis early in his NFL career, so too does Willis watch out for NaVorro Bowman. Bowman clearly can hold his own on the football field, but Willis helped ease the transition to a starting role this season - dispensing advice, offering encouragement, playing the big brother.

So when coach Jim Harbaugh gathered his players after practice Jan. 6 to deliver the news, Willis burst with pride. No, not when Harbaugh announced Willis had been named first-team All-Pro - that's practically an annual happening, cause merely for knowing glances.

Harbaugh also revealed the other first-team All-Pro inside linebacker - Bowman.

"It was special to see Patrick's reaction when he heard NaVorro got it," said rookie guard Daniel Kilgore, whose locker at the team's Santa Clara headquarters sits between Willis' on one side and Bowman's on the other. "I was watching them. It was awesome to see Patrick more excited for NaVorro than he was for himself."

This tandem will play a significant role in Sunday's NFC Championship Game against the New York Giants. Justin Smith anchors the defensive line and Donte Whitner roams the secondary, sure, but Willis and Bowman patrol vast frontiers of grass in between, reliably covering tight ends and relentlessly chasing down running backs.

Bowman - only 23 years old, in his second year from the school (Penn State) once known as Linebacker U. - led the 49ers with 173 regular-season tackles. Willis added 97, racing to the ball with customary swiftness and vigor.

Willis, 26, is a perpetual All-Pro, but there was no guarantee how Bowman would perform in his first year as a starter. Spikes' departure to San Diego created the vacancy, and Bowman quickly grew comfortable alongside Willis.

That did not happen by chance. Bowman didn't make himself available for this story, but he spoke about the influence of Willis (and Spikes) during a recent appearance on ESPN's "Rome is Burning."

"Both of those guys took me under their wing last year," Bowman said. "For me and Patrick to have the chance to be out there together this season, he's done nothing but help me on the field. ...

"We're a team out there. Pat's great - he's been doing it for a long time - but as he says, he's not perfect. We help each other out there, and it's been working out for us. We don't have egos. We're glad to be playing next to each other."

The process began in earnest during training camp. Willis and Bowman were roommates, giving them a chance to get to know each other better - beyond the impending starter learning from the established star on the field.

"We bonded really well," Willis said. "Any time he's had a question, he doesn't mind asking me and vice versa. We're in this together. We're always looking for a way to help one another."

Willis' demeanor no doubt makes this dynamic possible. He brings a glamorous track record to work every day - five Pro Bowl berths in his five years in the league, plus first-team All-Pro recognition in four of those five seasons (he was named to the second team in 2008).

But Willis doesn't lord his credentials over Bowman or anyone else in the locker room. He goes about his business quietly and purposefully, relishing Bowman's success as much as his own.

"Any time he makes a play, I try to be the first one there to tell him, 'Good job,' " Willis said. "When we're watching film the day after a game, I see him make a play and tell him that was a good tackle or a good shed. I always try to be supportive and let him know I'm watching every play."