BOSTON (AP) -- Tamerlan Tsarnaev ranted at a neighbor about Islam and the United States. His younger brother, Dzhokhar, relished debating people on religion, "then crushing their beliefs with facts."
The older brother sought individual glory in the boxing ring, while the younger excelled as part of a team. Tamerlan "swaggered" through the family home like a "man-of-the-house type," one visitor recalls, while Dzhokhar seemed "very respectful and very obedient" to his mother.
The brothers, now forever linked in the Boston Marathon bombing tragedy, in some ways seemed as different as siblings could be. But whatever drove them to allegedly set off two pressure-cooker bombs, their uncle is certain Dzhokhar was not the one pulling the strings.
"He's not been understanding anything. He's a 19-year-old boy," Ruslan Tsarni said of his brother's youngest child, who is clinging to life in a Boston hospital after a gunbattle with police. "He's been absolutely wasted by his older brother. I mean, he used him. He used him for whatever he's done. For what we see they've done. OK?"
Criminologist James Alan Fox says the uncle's intuition is justified. In cases like this, he says, it is highly unusual for the younger participant -- in this case, a sibling -- to be the leader.
"I would be surprised," says Fox, a professor of Criminology, Law and Public Policy at Boston's Northeastern University. "Very surprised."
Whatever their fraternal pecking order, when the bullets began flying in Watertown on Thursday night and 26-year-old Tamerlan went down, his younger brother ran him over -- dragging him for about 30 feet -- before ditching the car and fleeing on foot. After a 24-hour manhunt that shut down most of the Boston metropolitan area, police cornered the gravely wounded Dzhokhar hiding in a boat in a backyard, only blocks from where his brother bled out.
Officials said Dzhokhar was in serious condition Saturday, unable to communicate. So, at least for now, investigators and the public are left with only enigma.
The ethnic Chechen family came to this country in 2002, after fleeing troubles in Kyrgyzstan and then Dagestan, a predominantly Muslim republic in Russia's North Caucasus. They settled in a working-class part of Cambridge, where the father, Anzor Tsarnaev, opened an auto shop.
He returned to Dagestan about a year ago.
Luis Vasquez went to high school with Tamerlan and later helped coach Dzhokhar's soccer team at Cambridge Rindge and Latin. With the father gone, Vasquez said, the older brother assumed a kind of paternal role, at least where the girls in the family were concerned.
"He was very protective of his (younger) sister, Bella," Vasquez said. "He would keep an eye out, making sure she's good, making sure she's not having a hard time."
Vasquez chalked it up to "his culture" and "what his family expected out of him."
David Mijares, who trained in boxing with Tamerlan in high school and later coached the younger brother in soccer, agreed that his friend felt pressure to take his father's place.
"He had to be a man at a very early age," says Mijares. "That would be, in my opinion, a huge reason for who he was, all serious and no nonsense."
John Pinto said the pair were frequent patrons at his Midwest Grill, just a couple of blocks from their house. When they walked in, he said, Tamerlan was always in the lead.
"I think the big brother is more the command guy, boss," Pinto said, puffing out his chest for emphasis.
That said, Dzhokhar was very much his own man. While he would tag along to Tamerlan's boxing practices, the younger brother was into wrestling.
In one of his tweets, he complained that his mother was trying to arrange a marriage for him, as she'd done for his sisters.
"she needs to (hash)chillout," he tweeted on July 12. "i'll find my own honey."
Tamerlan preceded his brother at the prestigious Cambridge Rindge and Latin High School, which counts celebrities Matt Damon and Ben Affleck among its alumni. But he does not appear to have been a standout student and athlete whose reputation Dzhokhar would have felt pressure to live up to.
"To be perfectly honest, I did not know he HAD an older brother from the start," said classmate Alexandros Stefanakis, who played pickup basketball games and hung out with Dzhokhar outside school.
Anne Kilzer of Belmont would go to the Tsarnaev home for regular facials from the boys' mother, Zubeidat. She said the older brother was a "macho guy," whereas Dzhokhar seemed more cerebral.