Six Nations: Italy braced for a double helping of Vunipolas when they play England at Twickenham

Mako and Billy are both poised to feature for England – and they are hungry for some action

Mako (left) and Billy Vunipola at Pennyhill Park yesterday (Getty Images)

If England's opponents regard the selection of one Vunipola in the red-rose pack as deeply unfortunate, two Vunipolas will amount to a conspiracy. Much to their consternation, this is the shape – a very large shape – of things to come. Mako, the 20st Saracens prop, has already made his substantial presence felt at international level, although the Tongan has yet to start a Test for the country he now calls his own. Brother Billy, the uncapped Wasps back-rower who thinks he may just be the heavier of the two these days, is not far behind in the pecking order.

Both have played a significant part in England's planning for this weekend's Six Nations meeting with Italy at Twickenham, with Mako among those widely tipped for promotion to the starting line-up – the Gloucester centre Billy Twelvetrees, the Harlequins scrum-half Danny Care, the Leicester hooker Tom Youngs and the Wasps flanker James Haskell being the others – and Billy in the running for a breakthrough appearance on the bench. Pity the poor Azzurri. They must be dreading it.

The Vunipolas have not faced each other in anger since their mid-teens – had they done so, seismologists around the world would surely have noticed – but they have been the talk of the coaching community for years. The rapid rise through the ranks may have bewildered both men, but those age-group selectors who first saw them throwing their pounds and ounces around the playing fields of England are not surprised in the least. They felt that if the two of them could get themselves fit, they were racing certainties for top honours.

"We were definitely heavier then than we are now – and definitely bigger than most kids our age," said the 22-year-old Mako. "It was our under-18s coach, Neil Taylor, who said we'd have to shed some pounds if we wanted to play at a high level."

Twenty-year-old Billy then put some flesh on the bone, so to speak. "We went through a spell of not having breakfast or lunch, but coming home after training and feasting on whatever food was quickest to hand. Bread, potatoes… that kind of thing. We were big on the carbs, basically."

Between them they scaled down by the grand total of 36kg, but it has not been plain sailing on the fitness front. At the start of last season, Billy contracted pneumonia and ended up in hospital.

"I rang him, just to check he was all right and see if he needed anything," Mako recalled. "He said: 'Bring me some food,' so I took him a KFC." Did he have to sneak it past the nursing staff? "No, I just walked straight in."

Sadly, Billy did not walk straight out. "I managed to burn my back by falling asleep on a hot water bottle," he said, "and the burns became infected. I spent a long time on strong antibiotics." Did he not notice that the water in the bottle was just a little hotter than usual? "I'd been up all night because of the pneumonia, so I was really tired," he explained. "When my mum made a hot water bottle for me, she always put a cover on it. I forgot about the cover."

Billy's injury and illness issues have continued to hinder him: called into the Six Nations squad in January, it is only in the last few days that he has been able to take an active part in preparations. "I've felt a bit awkward until now," he admitted. "I imagined the others saying: 'Here's this new guy and he's not even training. He's just here for the free food'. "

But Stuart Lancaster, the England head coach, believes the youngster has what it takes to join Mako in the match-day squad and is keen to put his selectorial instinct to the test.

That instinct is likely to be proved sound. Billy was asked to grow up very fast indeed last season, when Wasps called a number of profoundly inexperienced age-groupers into the front line during a bitter struggle against relegation, and the harsh realities of those desperate weeks accelerated his development.

"It was so stressful – the most stressful time I've had in rugby, by a long way," Billy acknowledged. "But it did a lot for my confidence. We were written off by people, but we came through it with the knowledge that we could play Premiership rugby with the older guys – that we were there for a reason.

"That confidence is important. When England won the World Cup in 2003, I remember watching Lawrence Dallaglio (the finest No 8 in the history of the Wasps club and another player who knew what it was to play like a veteran at a young age).

"He was so confident. I didn't really like him because of that, but looking back, I admire the fact that he always felt he could go out there and win the game for his country. He's still a big figure at Wasps. To wear the same shirt as he wore makes me feel proud."

Brothers-in-arms: Other England siblings

Ben and Tom Youngs

Scrum-half Ben has 31 England caps and was joined by elder brother Tom at hooker in last year's victory over Fiji.

Delon and Steffon Armitage

The duo played together five times for the national team between 2009 and 2010 but both have since fallen out of the team owing to problems with form or fitness.

Rory and Tony Underwood

Both pacy wingers, Rory and younger brother Tony featured during a successful spell for England. Rory played between 1984-96, overlapping with Tony's 1992-98.

Parisse set to give Italy a boost and Lions a test

Italy received a huge boost ahead of Sunday's match with England when their captain, Sergio Parisse was cleared to play by an appeals panel.

The man widely considered to be the most gifted No 8 in world rugby has had a 30-day suspension imposed for insulting a referee during a club outing for Stade Francais last month reduced to a 20-day suspension for "failing in his captain's duties". As a result, the ban will now expire on Saturday.

Parisse has also been named in the Barbarians squad for the match with the British and Irish Lions in Hong Kong on 1 June.

Four fellow internationals were confirmed by the Baa-Baas selectors: the World Cup-winning Springbok centre Jaque Fourie, Northampton's Samoan scrum-half Kahn Fotuali'i, the Italian prop Martin Castrogiovanni and the French back-rower Imanol Harinordoquy, who was one of the outstanding performers at the last World Cup in 2011.