Christine Ohuruogu won Britain's only athletics gold medal in Beijing
World and Olympic champion Christine Ohuruogu looks set to have tough opposition at the 2012 Games, in the shape of 15-year-old sister Victoria.
UK Athletics chief Niels de Vos has predicted an Ohuruogu one-two in 2012 400m final.
Victoria, 15, told BBC Radio 5 Live: "She's my sister but I won't take that into consideration. I want to win."
But Christine insisted: "It doesn't matter who wins. Everything we can do to make the family proud is good."
Last year Londoner Christine, 24, became a household name as she added an Olympic gold medal to the world title she claimed in Osaka in 2007, as well as making the BBC Sports Personality shortlist for the second year in a row.
Ohuruogu told 5 Live's London Calling programme that 2008 was a "great year" and how she was encouraging her younger sister, who is about to step up from the 300m to 400m, to progress in the sport.
There are eight children in the Ohuruogu family - all of whom were screaming at the television when Christine crossed the line in August.
Victoria is a star in the making after a silver at the English Schools and winning at the AAA Championships.
But she said: "I don't really let the pressure get to me. You just have to do what you've got to do."
Christine added: "I tell Victoria that when I made my Olympic debut I was 20 - she'll be 19. What I've done is what I've done and I've told her she has to make a name for herself.
"I encourage her and people of her age just to go for it. She needs to work hard and keep the Olympics in her sights, but it's not the be all and end all."
Having just returned from warm-weather training in South Africa, Ohuruogu is preparing for the World Championships in Berlin in August with her first action this year at the Irish Indoor Championships in February.
On the prospects of retaining her 400m Olympic crown in front of a home crowd by beating her sister, she added: "Everything we do, we do it for the family - regardless of who wins.
"Our surname is what people will see. But I don't really think about 2012 too much.
"Every year will be a stepping stone and hopefully come London I will have enough experience and knowledge to know how to deal with the pressure."
Victoria added: "It's even better because it's down the road from where we live. The family will be close and it will be really good if both of us are there."
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