Former foreign secretary is to embark on his first major task for Labour by meeting university students.
After talks between the brothers, whose relationship was put under intense pressure by the battle last year, David Miliband has agreed to tour universities across Britain to meet students.
He will hold question and answer sessions at more than 20 campuses over the next 12 months in a move that will be widely viewed as the first steps to an eventual return to frontline politics.
David Miliband said: "I am looking forward to helping Ed build the foundations for success at the next general election by listening to students and encouraging them to see Labour as the voice for Britain's future in these tough times.
"By getting involved in Labour Students' Living Wage campaign I know we can make a real difference on the campuses of Britain.
The events will be hosted by politics and international relations departments and will cover domestic and global issues.
Mr Miliband will also promote Labour Students' national campaign for a "living wage" for employees at higher and further education institutions across the country.
His own venture, The Movement for Change, which aims to train future leaders, will also support the campaign.
Labour leader Ed Miliband said: "I am delighted David is taking on this role. He is a big asset to the Labour Party and I am confident he can bring our message to campuses up and down Britain.
"This builds on work which he was already doing with universities and I know that in this role David will help our party as we look outwards to engage people - particularly the next generation - so that we can face the future with hope.
The party was hosted by Rupert Murdoch's daughter Elisabeth and her husband Matthew Freud in Burford on Saturday, July 2.
Mr Alexander also met the couple in London at a "social" event on December 20, the document reveals.
Shadow Northern Ireland secretary Shaun Woodward met Mrs Brooks on Boxing Day. It emerged earlier this month that Prime Minister David Cameron, who succeed Mr Woodward as MP for Witney after he quit the Tories and defected to Labour, also had a social engagement with Mrs Brooks on December 26.
Mr Woodward also met up with Mrs Brooks in France on June 11 this year and visited Mr Hinton on October 9 in the United States of America.
Tessa Jowell, shadow Olympics minister, also attended the party although she declared the date as July 3. The bash, held at Burford Priory, reportedly started on Saturday evening and continued until noon the next day.
Ms Jowell also met the couple at social events in London and Oxfordshire on December 1, Christmas Eve and Boxing Day.
Ed Miliband had previously released a list of the meetings he had held since taking the top job last September but today's records date back to May and cover all the party's senior politicians.
They show Mr Miliband has attended more than 50 meetings or receptions with proprietors, editors and senior media executives, including senior figures from the BBC, ITV, the Daily Mirror, the Daily Telegraph, The Independent, The Observer, The Times and The Guardian.
It follows the release by Government of all ministerial contacts with senior media executives. That showed Chancellor George Osborne had met executives of News Corporation companies on 16 occasions since the coalition Government took power.