Tributes have been paid to an "exceptionally talented" political campaigner who died in a seaplane crash in Australia on New Year's Eve.
Will Cousins, 25, head of press for Open Britain, which opposes a hard Brexit, died alongside his father Richard, 58, and his brother Edward, 23.
Emma Bowden, 48, who was Richard's fiancee, and her 11-year-old daughter Heather Bowden were also killed in the crash off Jerusalem Bay near Cowan, 25 miles north of Sydney centre, at about 3.10pm (4.10am GMT) on Sunday.
Labour MPs said Mr Cousins, who worked on the Remain campaign during the referendum, was an "absolute joy" to work with and would be "missed by all".
Former shadow chancellor Chris Leslie? said: "Such awful news - a devastating family tragedy. Will Cousins was exceptionally talented head of press for @Open_Britain and he'll be deeply missed by all. Many condolences to his friends, family and colleagues."
Mary Creagh, a Labour former frontbencher, said: "So very sad to hear of the loss of brilliant Will Cousins. His family, friends & @Open_Britain colleagues are in my thoughts & prayers."
Labour MP Wes Streeting said: "Truly awful news about Will Cousins and his family. Such a good and talented guy. Sending love to everyone, especially the @Open_Britain family."
Labour former frontbencher Alison McGovern said: "Absolutely devastated. Thinking of all who loved him. Worked with Will over recent months and he always made me laugh, but was so very smart. An absolute joy to work with."
Open Britain chairman Roland Rudd said Mr Cousins was an "extraordinary young man" who would be "missed beyond words".
"All of us at Open Britain are devastated by the tragic loss of Will and his family," he said.
"Will was an extraordinary young man who was passionate about what he did; who took deep pride in his work; and came into the office every day with enthusiasm, energy and determination.
"Will saw his role at Open Britain as more than a job. For him, it was a cause akin to a crusade to stop Britain crashing out of the EU with no deal or a bad deal.
"Will was a great team player who loved the camaraderie of our young team and developed close relationships with all his colleagues. He will be missed beyond words."
James McGrory, executive director of the group, said: "The dreadful news about Will and his family has left all of us at Open Britain in shock and deep sorrow.
"Will was one of the most impressive people you could ever work with. His ability, dedication and passion were an inspiration to everyone around him. At such a young age, he had mastered skills that elude many for their entire careers.
"We have not just lost a special colleague but a wonderful friend. Will's razor-sharp wit, easy company and generosity will be missed even more than his huge brain, peerless prose and fearless ideas.
"Words cannot express how much I and the rest of the team at Open Britain will miss Will. We have lost a brilliant colleague and a true friend."