The Manchester City midfield player told his brother Michael, 18, who has been named by Merseyside Police as an individual wanted for questioning: "You must do this for the Walker family so they can mourn Anthony and because you know it is the right thing to do."
The player, aged 22, described Anthony's murder, by attackers who embedded a pickaxe in his forehead, as "horrific" and "senseless". Mr Barton made it clear that he had not been brought up with his brother and said that his "side of the family" were "sickened" by the death of a "kind, decent young man".
Joey Barton was brought up by his father, Joey Snr, a roofer, who split 10 years ago from the player's mother, Rita. She brought up Michael and his twin brother, Andrew. Another man named by police as a suspect in the murder investigation 20-year-old Paul Taylor is a first cousin of the Barton boys. His mother is Rita's sister.
Police believe that Michael Barton and Mr Taylor may have fled to Amsterdam or Spain, or somewhere else on the Continent. They seem to have had the financial means to travel such a distance, but they are unlikely to have travelled any further. Both have previous criminal convictions.
Joey Barton spoke last year about his upbringing on the tough St John's estate in Huyton, Merseyside, where the murder took place. The same estate has produced the current Liverpool captain Steven Gerrard and the former Everton and England player Peter Reid. "St John's is quite a rough council estate," he said. "We played football wherever we could. We made goals out of wood, scaffolding, anything. The estate is not as bad as it [seems] to outsiders [but] it has got problems with drugs and crime."
Hundreds of people attended a vigil in memory of Anthony yesterday at St George's Hall in Liverpool. Anthony's mother, Gee, made her first public statement since her son's murder in Huyton, Merseyside last Frida.
"When I look at the sea of faces, so many close people I know, I am so overwhelmed that I am not sorry that I came here," she said. "I have to tell you about Anthony, he was everybody's son. I am sure he is looking down at you all bouncing his basketball.
"I am receiving letters from people I don't know from America, from Canada, phone calls from ireland, you name it and letters of condolence."
She appealed for witnesses to come forward, saying she was sorry for the attackers "don't deserve to walk the streets".
Anthony's older sister, Dominique, was fighting back tears as she issued an appeal for help in catching her brother's killers. "This is no joke, he is flesh and blood, my only brother, he was only 18. It's not over," she said.
Monica Binns, Anthony's aunt, said the teenager's family had faced racism through more than 18 years on Merseyside. While visiting the shrine, she said: "We've had racism on the bus, going to the shop and school. We take it in our stride because every day we go outside it's in your face."
Doreen Lawrence, the mother of Stephen Lawrence who died in a racist attack in 1993, visited the scene of the killing and attended the vigil. "How many more young people have to die before society makes changes?" she said. "Why should another family suffer the way we did? I'm only hoping that this time justice will be done," she said.
Anthony was at a bus stop with his white girlfriend, Louise, and his cousin Marcus Binns, both 17, when he was racially abused by a man standing in a car park of the Huyton pub opposite. To avoid confrontation, they took a short cut through McGoldrick Park, where Anthony was attacked.
Officers are examining a Peugeot car removed from the pub forecourt and are also seeking evidence from the relatively small number of people in the pub on Friday night including six who were at the pool table.
Detectives are also trying to enhance imprecise CCTV images.
The player's statement
"The horrific killing of Anthony Walker has shocked the country. Those responsible for the senseless death of a kind, decent and caring young man must be brought to justice. My sincere condolences go out to Anthony's family during this terrible time.
My side of the Barton family are sickened by his death. Although Michael and I were not brought up together I urge him now to come forward and give himself up to the police and help them with their investigation.
Michael, if you have any information about what happened you have to tell the police. You must do this for the Walker family so they can mourn Anthony and you must do this because you know it's right."Reuse content