Dame Julia has previously shared details of her busy day-to-day life, which saw her regularly working between 6am and midnight as well as walking her dog near home in South Kensington.In a 2006 interview, she said she enjoyed escaping by reading, and “the great relief of being with precious people who have nothing to do with the art world”.“In truth, when I’m out in the world, I don’t escape very much from the job,” she said then.The Evening Standard reported Dame Julia had recently told those close to her she had been considering starting a family for some time.Her friend, the financier Robin Saunders, told the newspaper: “This is the most exciting news! Julia will be a wonderful mother and role model for her daughter. I wish her happiness with Pia.” The redeveloped Serpentine Sackler Gallery in Hyde Park in 2013 After retiring from one of Britain’s most successful galleries at the top of her game, Dame Julia Peyton-Jones could have been forgiven for putting her feet up.But the former head of the Serpentine Gallery is unlikely to be getting much rest in the near future, after it emerged she has welcomed a new baby.Dame Julia, 64, has had a baby girl named Pia, her first child.The news was welcomed by friends of the director, who suggested it may have surprised an art world wondering what she was going to do next.Dame Julia left the Serpentine in the summer, saying at the time that she planned to pursue her own artistic interests and go travelling.She has now welcomed a daughter, with friends saying she will be a “wonderful” mother.A spokesman for Dame Julia, who is currently in America, confirmed she had welcomed a baby, but said she did not wish to share further details about the new arrival. It is understood she plans to return to London, where she is a popular and prominent member of the arts scene.Dame Julia has not named the baby’s father, or confirmed a relationship.One friend said: “Everybody had been wondering what she was going to do next, and this is absolutely lovely.“Everybody is thrilled for Julia and she will be a wonderful mother.”Dame Julia had spent 25 years building the Serpentine into one of the world’s most successful galleries, admitting last year that there was “never a good time to leave”.“I wanted to go when the Serpentine was firing on all cylinders and our major capital projects had been completed,” she said. “I felt after 25 years this was a good time to hand over the reins to someone new.”Her motto, along with her co-director Hans Ulrich Obrist, had been “to think the unthinkable”. Julia Peyton-Jones with actress Kate Hudson at a Serpentine party Dame Julia with Hannah Rothschild, chair of the National Gallery’s board of trustees Speaking at her leaving party in June, she told friends she would be pursuing her own art again, after choosing to put her successful creative career aside to take on lecturing, curating and directing roles.Then, she told the Telegraph she planned to take a holiday in Australia to view Aboriginal cave paintings for a “fresh” adventure which would “give me a lot to think about”.In June 2016, she was awarded a damehood for services to the arts in the Birthday Honours list.At one time, Dame Julia had been tipped to take on the role of director of Tate after Sir Nicholas Serota announced he was stepping down, but friends said last year that she was enjoying her time away from running an institution.Maria Balshaw, the director of Whitworth Art Gallery and credited with transforming the Manchester arts scene, has now been confirmed in the Tate role. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.