Profile: Hilary Benn steps out of late father's shadow
The odds on Hilary Benn becoming the next Labour leader dramatically shortened after his headline grabbing Commons speech in favour of Syria air strikes - but who is he?
If the Labour Party has an aristocracy, then the Benn family must take pride of place.
Ever since Hilary's grandfather abandoned the Liberal Party almost 90 years ago, there's been a Benn in Labour's highest counsels.
Each Labour prime minister, all six of them, has had a Benn in his cabinet.
Clement Attlee made that grandfather an hereditary peer; Hilary's father Tony fought an ultimately successful battle to disclaim the Stansgate title.
After Tony's death, Hilary's older brother took it up, though these days being Viscount Stansgate no longer carries with it an automatic seat in Parliament.
Hilary entered the Commons in 1999 after winning a by-election in Leeds. Yet, 16 years an MP, he's continued to toil in the shadow of his late father.
That, according to Steve Richards, political columnist with the Independent, adds an extra tension to the relationship between Hilary and the party leader.
"Jeremy Corbyn idolised his [Hilary's] father Tony, and remains close to many members of the Benn family," says Richards.
"And yet, one way or another, Corbyn's rise to the leadership has given Hilary Benn definition against this figure who so adored Tony."
Tony Benn famously and frequently excoriated those who called for war.
After Hilary's Commons performance on Wednesday, social media was awash with descriptions of Benn senior "turning in his grave".
Yet the speech would not have surprised him; after all, Hilary voted for the invasion of Iraq in 2003.
David Blunkett, who employed Hilary as one of his advisers when he became a cabinet minister in 1997, thinks those who seek to reproach the son by invoking the father misunderstand the relationship.
"I remember when Hilary made his first frontbench speech as a member of my team. His dad was in the gallery - people were describing the tears in his eyes.
"He was so proud of Hilary, and he was proud of him being his own person. I think there is a real message in that for so many people in the Labour Party, including those in Parliament, which is they've just got to be their own person."
Besieged by reporters the morning after his now famous Commons speech, Hilary drew attention away from the politics, and the gaping wound of Labour division: "Now that the House of Commons has made its decision, having heard all of the arguments, all of our thoughts today are with the brave men and women of the Royal Air Force and we pray for their safe return."
His father had been an RAF pilot in World War Two; even his grandfather, then in his 60s, had flown combat missions. So Tony Benn, always a devoted parent, would probably have approved that sentiment.
Still, he calls himself a Benn but not a Bennite, a phrase that helped him as he began his parliamentary career, poised in a politically precarious way between his left-wing antecedents and new New Labour in its pomp. He's steeped in the party - first a union official then a London councillor.
His instinct is loyalty, his manner courteous and low key.
"Unlike some of us, he doesn't drink, he doesn't swear, and he doesn't smoke. And there's only one of those I don't do and I'm not telling you which one it is," says David Blunkett.
That might make him seem a little dull. He's certainly reliable and remarks like these, just after Jeremy Corbyn was elected, may have reassured Labour's new leader that he could be trusted: "It's a much more honest and open approach... Jeremy will treat those who have a different view to him with respect, as we will treat him with respect."
That respect must have been sorely tested in recent days. Hilary doesn't lack for ambition; eight years ago, he ran for deputy leader.
Even the most loyal of politicians could be forgiven for letting their imagination soar after the sort of reception Hilary Benn received on Wednesday night.
Spontaneous applause erupted around the Commons chamber; "outstanding" one MP cried. The minister Hilary Benn shadows, Philip Hammond, the foreign secretary, called it "one of the truly great speeches in parliamentary history".
During that speech, as he became more impassioned, arms subconsciously jerking just as Tony Benn's used to do, as he invoked Labour's internationalist tradition, its historic opposition to fascism, Jeremy Corbyn sat to his side with barely concealed fury.
He shifted his bottom to accommodate Benn as he sat back down but, at least until the TV cameras cut away, the two men did not acknowledge one another.
Steve Richards, of the Independent, isn't the only one wondering if Jeremy Corbyn stumbles whether a Benn might finally grab the Labour crown.
"I think he's probably got more of those qualities than the relatively young figures being talked about as alternatives, but it doesn't mean that he becomes ready-made as a leader capable of uniting a deeply divided party.
"But he might be better placed than anyone else."