Constant companions as boys, M.J. Stewart and Arturo Brown would daydream about playing football together in high school, maybe even college. Both only children named after their fathers, the pair became the brothers that neither had.

“They just have that relationship where they’re inseparable,” Brown’s mother, Kendra, said. “The left hand, the right hand. That’s how they’ve always been.”

They assumed their glory days would extend from their various Arlington County youth teams and then the Beacon House Falcons in the District, but in seventh grade, Brown left Williamsburg Middle School and moved to Stafford County with his mother. He later attended Brooke Point High.

Stewart, a grade younger, remained in Arlington and enrolled at private school O’Connell as a freshman.

But when Yorktown faces South County in a Virginia AAA Northern Region Division 5 semifinal Friday, the No. 11 Patriots will be led by the reunited duo of talented running backs.

Stewart left O’Connell to attend Yorktown his sophomore year, and several weeks later, Kendra Brown allowed her son to move back to Arlington to live with his father and attend Yorktown, seeking a fresh start after his grades had slipped at Brooke Point.

Brown arrived too late to play for the team last year, but this fall, he and Stewart have helped the Patriots post a second consecutive unbeaten regular season.

So Stewart and Brown went from a tandem as kids, to miles apart, to lining up in the same backfield and in the same secondary for one precious season. The two are so inseparable, they even sleep in the same room during the many nights Brown spends at Stewart’s home with M.J. and Marvin Stewart Sr.

“They’re not blood-related, but they’re brothers,” Yorktown junior quarterback Will Roebuck said. “They’re as close as it gets.”

It’s just like the old days, only with higher football stakes and a heightened appreciation.

“Life is crazy,” Brown said one day recently after practice. “It’s a small world. It’s great being back with him, coming back to the same place where I grew up.”

“I always thought he would come back,” Stewart said in a separate chat. “Just the fact that we’d been playing for a long time together, and I thought eventually our paths would cross again. And thank God they did. We’re just so close and he’s like a brother to me. So it’s nice to play with a brother, you know?”

Their paths, or running lanes, indeed cross on the field. The 5-foot-8, 167-pound Brown, shifty and powerful, would be the featured back on many teams but moved to fullback to yield to the 5-foot-11, 182-pound Stewart, a sleek recruit with several ACC scholarship offers.

Together they have combined for 2,030 rushing yards and 28 touchdowns on 246 carries. They also have six touchdowns between them on 22 receptions, and while Brown’s contributions have cut into Stewart’s stats, they have made for a fresher top back. Despite averaging just 14 carries per game, Stewart is the National District offensive player of the year; he and Brown are first-team all-district defensive backs.

In the secondary, Stewart plays safety and Brown cornerback. In the fourth quarter of a tight game against Langley last month, Brown tipped a pass that Stewart returned 70 yards for a touchdown.

“It really helps that we have one at corner and one at safety, a lot of times on the same side,” Yorktown assistant Wayne Hogwood said. “The communication aspect and them playing off each other is a good thing for us. Not to mention they’re a little bit competitive. If one guy makes a good play, he’s encouraging to the other guy who wants to go out and make a big play as well. They’re each other’s biggest fan and biggest supporter, and that’s pretty cool, especially when you’re splitting carries.”

The boys’ personalities are different. Brown, voted to the senior homecoming court despite being at Yorktown for only a year, is more extroverted and often breaks down post-practice huddles with one of his crazy dances. Stewart is more reserved and observant. Both are sneakerheads; Brown has 26 pairs.

They have only one class together — physical therapy — but complement each other academically. Brown calls Stewart a “math whiz,” and Stewart considers Brown an idea man. When Stewart needed to draw a War of 1812-themed political cartoon for his Virginia history class, Brown suggested a Christmas setting with Native Americans opening gifts of weapons from the British to use against the colonists.

Yorktown Coach Bruce Hanson would have liked to have instructed the tandem sooner. He first observed Brown when Brooke Point and Yorktown were at the same University of Virginia camp four several years ago. He could not understand why so many of his players knew the little rising Brooke Point freshman who was darting all over the field. Told that Brown, who would go on to start for Brooke Point as a ninth-grader, was a former Arlington student, Hanson had to get the full story.

But he did not know Brown had arrived at Yorktown until the player surprised him last October. It was too late to suit up for the Patriots, but Brown hung out at practices and other team gatherings and mentally geared up for his senior season, which has so far been everything that either Brown or Stewart could have wanted. Yorktown is chasing its first state playoff berth since 1999.

“I didn’t see it coming,” Kendra Brown said of the unlikely reunion. “But their little dream did come true.”