NEW YORK — Preparing to coach the Baltimore Ravens in the AFC championship game Sunday night, John Harbaugh watched on the stadium’s big video screen as Jim Harbaugh’s San Francisco 49ers wrapped up their victory in the NFC championship game.

John looked into a nearby TV camera, smiled broadly and said: “Hey, Jim, congratulations. You did it. You’re a great coach. Love you.”

Less than four hours later, the Ravens won, too. Some siblings try to beat each other in backyard games. These guys will do it in the biggest game of all. Yes, get ready for the Brother Bowl.

It’ll be Harbaugh vs. Harbaugh when Big Bro John’s Ravens play Little Bro Jim’s 49ers in the Super Bowl at New Orleans in two weeks.

As much chatter as there will be about the players involved — from Ravens linebacker Ray Lewis and his impending retirement to 49ers quarterback Colin Kaepernick’s sudden emergence — the Harbaugh family angle will make this coaching matchup the most scrutinized in the nearly half-century of Super Sundays.

The Harbaughs’ sister, Joani Crean, wrote in a text to The Associated Press: “Overwhelmed with pride for John, Jim and their families! They deserve all that has come their way! Team Harbaugh!”

Who’s a parent to cheer for?

During the 2011 regular season, the Harbaughs became the only brothers to coach against each other in any NFL game (the Ravens beat the 49ers 16-6 on Thanksgiving Day that year).

Now they’ll be squaring off with a championship at stake in a Super Bowl filled with firsts — and one truly significant last.

It will be the first one between coaching brothers, of course. First one for Joe Flacco, the oft-doubted Ravens quarterback with the superb touch on deep balls and a QB-record six postseason road wins. First one for Kaepernick, the second-year player with the tattooed arms, the sprinter’s speed, and a shoulder that zips throws like the high school baseball pitcher he used to be.

And it will be the last game for 17-year veteran Lewis, Baltimore’s emotional leader and this postseason’s top tackler with 44 so far.

“This is our time,” Lewis pronounced.

He appeared to be on the verge of tears before and after helping Baltimore become the only team in 68 tries to overcome a halftime deficit against Patriots quarterback Tom Brady in Foxborough, Mass.

The NFC West champion 49ers (13-4-1) open as 5-point favorites, seeking a record-tying sixth Super Bowl title but first since 1995. The franchise of Hall of Fame quarterbacks Joe Montana and Steve Young is 5-0 in Super Bowls.

The AFC South champion Ravens (13-6) are headed to their second Super Bowl; Lewis was the MVP when Baltimore beat the New York Giants in 2001.

With Kaepernick’s terrific passing — he was 16 of 21 for 233 yards and a touchdown in only his ninth career NFL start — and two TD runs by Frank Gore, San Francisco erased a 17-point deficit to beat the Atlanta Falcons 28-24 Sunday.

Baltimore then fashioned a comeback of its own by scoring the last 21 points to defeat the New England Patriots 28-13, thanks in large part to Flacco’s three second-half touchdown tosses, two to Anquan Boldin.

In the often risk-averse NFL, each Harbaugh made a critical change late in the regular season in a bid to boost his team’s postseason chances. Clearly, both moves worked.

After 49ers quarterback Alex Smith, the starter in last season’s overtime NFC title game loss to the New York Giants, got a concussion, Jim switched to Kaepernick for Week 11 — and never switched back. Now San Francisco has its first three-game winning streak of the season, at precisely the right time.

Baltimore, meanwhile, was in the midst of a three-game losing streak when John fired offensive coordinator Cam Cameron and promoted quarterbacks coach Jim Caldwell to replace him.

The 50-year-old John is 15 months older than Jim and generally the less demonstrative of the pair, although John certainly did not lack intensity while making his case with officials a couple of times Sunday.

The ever-excitable Jim — who was treated for an irregular heartbeat in November — was up to his usual sideline antics in Atlanta.

He spun around and sent his headset flying when the original call stood after he threw his red challenge flag on a catch by the Falcons. He hopped and yelled at his defense to get off the field after their key fourth-down stop with less than 1 1/2 minutes left. He made an emphatic-as-can-be timeout signal with 13 seconds remaining.

Expect CBS to fill plenty of time during its Super Bowl broadcast with shots of Jim, that trademark red pen dangling in front of his chest, and John, who usually wears a black Ravens hat. Yes, that is sure to be a focal point, until they meet for a postgame handshake.