Over that nine-day stretch that the Eagles spent on the West Coast in December, playing in Seattle before their sojourn in Southern California ahead of a game against the Rams, Trey Burton set aside a night or two for what would seem a strange family reunion.

He visited his paternal grandparents, Larry and Ida Burton, meeting them for dinner at his aunt's house. Trey had seen Larry and Ida briefly two months earlier, during the Eagles' first trip to the Los Angeles area, when they played the Chargers, but this time he had the chance for a longer visit and more expansive conversation.

"We talked about life," he said. Such a discussion could cover any number of subjects, and theirs did, but there was one topic they dared not touch.

‘He left’

A 26-year-old tight end, signed as an undrafted free agent in 2014, Burton has gone from unknown to indispensable over his four years with the Eagles. He caught a career-high 37 passes last season. He caught a career-high five touchdown passes this season. On Saturday, he threw the key block to spring LeGarrette Blount for the Eagles' only touchdown in their 15-10 victory over the Falcons, the decisive play in the win that elevated them into Sunday's NFC championship game against the Vikings. Come the offseason, Burton will be a free agent, which means, whether he re-signs with the Eagles or joins another team, he will know a measure of wealth and success that are usually only the stuff of a boy's dreams.

He will share none of that wealth, none of that success, none of his current and subsequent joy and satisfaction with his father. B.J. Burton was the unmentioned and unmentionable topic at that December dinner. Trey was 13 when the two last saw each other. He did not ask where his father is, and his grandparents did not tell him. They never do.

"He left," Trey said. "My dad's parents are, like, hiding him because he owed years and years of child support. They move him around to different spots. It's kind of complicated, a lot of stuff going on. I don't ever really want to talk to him."

Eagles-Vikings NFC championship: Special section preview

Larry Burton was himself a famous and accomplished athlete: an elite sprinter who tied the world record in the 60-yard dash, won an NCAA championship in the 200 meters, and finished fourth in the 200 at the 1972 Olympic Games in Munich; a star wide receiver at Purdue whom the New Orleans Saints selected with the seventh overall pick in the 1975 NFL draft. But it was Larry's post-football life that had to lend the scene of his sitting across from his grandson, neither of them bringing up the man who bridged them by blood, such odd irony. Larry retired from the NFL in 1980, then moved to Nebraska, his born-again Christianity calling him to minister to troubled youth at Boys Town. He and Ida lived there for 13 years, mentoring fatherless children.

"What you learn right away is that trouble has no boundaries," Larry said in the Dec. 21, 1992, issue of Sports Illustrated – in an article published 14 months after Trey was born. "I've had a kid living in this house who had nothing to his name except one comic book, and I've had a kid whose father made three million dollars a year. There's no difference. If there's trouble, there's trouble. You try to help."

When Trey was 8 years old and growing up in Venice, Fla., his mother, Cindy, would send him and his younger brother, Clay, to California every July, to stay with Larry and Ida for a month. It was an opportunity both for the boys to get to know their grandparents and for a single mother to regain some equilibrium in her life. The trips stopped when Trey turned 13. Football had begun to consume him by then, and any time away from the sport was too much time away.

It was then, Trey said, that B.J. tried to re-enter his sons' lives. John McClintock, their maternal grandfather, had been their primary male authority figure, making their lunches every day, taking them to school and picking them up. But now every Wednesday they were going to B.J.'s apartment, 20 minutes from their house, and staying with him until 9 p.m.

"So two months go by," Trey said, "and we go there on Wednesday, and we knock on his door, and he's not there. And we're like, 'Where the hell is this guy at?' We go to the front of the apartment complex and say, 'Hey, our dad's supposed to be this building.' And they say, 'No, he moved out two days ago.'"

The following Saturday, Trey and Clay were playing basketball at the local YMCA. A large glass window separated the court from the weight-training area. "We look up," Trey said, "and I said, 'Clay, is that our dad?' And Clay is like, 'Yeah, it is.' And then we look back, and he's gone." Trey swears now that, as his football career progressed from Venice High School to the University of Florida, he saw his father at several of his games, finding him in the crowded bleachers as if B.J. were a character in a child's seek-and-find book, a ghost who allowed his son only an occasional, maddening glimpse of a life that might have been.

Standards and obligations

"Nothing is given to anybody, and that is what Trey embodied," John Peacock, Venice High School's football coach, said in a phone interview. "He worked hard and did everything right. He was the perfect example, and a lot of times, you don't have the perfect example of that. This year, I had a player I had to mentor a lot, and I told him, 'Trey Burton has a story. His dad wasn't a part of his life.' Everyone has a story. What you do with your story is up to you."

You try to help, Larry Burton had said, right there in that magazine article. So how could that same standard not apply to the Burton men themselves? Didn't B.J. have an obligation to Trey, and shouldn't Larry have done what he could to make sure he fulfilled it? Maybe he did. Who can know? Trey is married and has three children, and he said he does everything he can to be nothing like his father, to meet and exceed his obligations as a parent. "The love I have for my kids, how involved I want to be," he said, "I don't think I would have appreciated it as much if I hadn't gone through that."

How, then, can he keep the relationship he has with his grandparents cordial? How could he keep it distinct from the relationship he doesn't have with his father?

"That's his choice," Trey said. "That's my dad's choice. My grandparents didn't choose for him to not be in my life. You've got to give a little grace. …

"It's not really awkward between us because I don't make it awkward. I don't care enough to hold a grudge on them. Normally, people look at me like, 'Dude, you're crazy, why are you still talking to them?' But they're my family, whether I like it or not. That's the way I look at it."

Trey Burton has never seen, or thought he has seen, his father at any of his games with the Eagles, so he has no reason to look to the Lincoln Financial Field stands Sunday, even if he wanted to. There's a phone number listed for Lawrence and Ida Burton in Rancho Santa Margarita, Calif. I called the number Monday, listened to a recorded greeting, identified myself as a writer, and left a message asking if they'd be available to speak about their grandson. I called back Tuesday. I called back Wednesday. The phone rang and rang and rang.

Get insights on the Eagles delivered straight to your inbox with Early Birds, beat writer Zach Berman's newsletter for Eagles fans. Click here to sign up.