Rod Stewart and his bikini-clad wife Penny Lancaster relaxed on a lavish superyacht with their children during a sun-soaked Ibiza getaway on Sunday.Penny, 55, looked incredible in a barely-there royal blue bikini while she rinsed off the salt water after taking a dip in the sea.Penny made the most of the hot weather as she topped up her tan on the sundeck, covering her age-defying physique with a long, navy blue striped shirt and baseball cap. The rockstar, 81, kept cool in a white linen shirt as he enjoyed an afternoon in the sunshine with his family. While the singer and his wife chatted to friends, his thrill-seeking sons plunged into the ocean after flying off the top of the superyacht. Rod Stewart and his wife Penny Lancaster relaxed on a lavish superyacht with their children during a sun-soaked Ibiza getaway on Sunday Penny, 55, looked incredible in a barely-there royal blue bikini while she rinsed off the salt water after taking a dip in the sea The rockstar, 81, kept cool in a white linen shirt as he enjoyed an afternoon in the sunshine His thrill-seeking sons plunged into the ocean after flying off the top of the superyachtThe couple met in 1999 and went on to have their first son, Alastair, 20, in 2005, before marrying in 2007, and welcoming their second son, Aiden, 15, in 2011. Rod is also the father to six children with four other women. His eldest child, Sarah, was born to his first serious girlfriend Susannah Boffey. He was just 17 when she was adopted in 1963, and she did not know she had a famous birth father until her adoptive parents revealed his identity when she turned 18. Father and daughter went on to build a relationship when Sarah was in her 40s. He then had daughter Kimberly, 46, and son Sean, 45, with his ex-wife Alana Stewart and a daughter Ruby, 38, with his ex-girlfriend Kelly Emberg.The Faces frontman had another two children, Renee, 33, and Liam, 31, with his ex-wife, model Rachel Hunter.Discussing how they first met, Penny revealed it wasn’t until nine months after exchanging numbers that Rod reached out to her.They originally met at a party at the Dorchester Hotel in Mayfair when Penny was studying photography at Barking College in Essex. They struck up a conversation and the singer asked her for her telephone number, which he gave to his bass player, Carmine Appice, for safekeeping.Still broken by his divorce from his second wife Rachel, his best pal decided that Rod wasn’t ready to meet the love of his life yet, so he withheld Penny’s number from the musician until he was in a better place. Penny made the most of the hot weather as she topped up her tan on the sundeck The age-defying star waved to her children who were enjoying a swim in the sea Rob stepped inside to escape the intense sun Penny looked incredible in the navy swimming costume The youthful Penny has two sons with Rod, Alastair, 20, and Aiden, 15 The family relaxed on the enormous superyacht One family member enjoyed thrill-seeking activities Two friends showcased their incredible figures in bikinis Penny couldn’t wipe the smile off her face on the family trip Rod and Penny’s son Alastair showed off his impressive strength skills Penny cooled off with a shower Rod’s son Liam, from his marriage to model Rachel Hunt, jumped off the superyacht The 31-year-old went head first into the ocean Alastair flexed his abs in pale blue swim shorts The family are staying on an impressive three-storey superyacht Liam’s sister Renee battled her nerves ahead of the thrill-seeking stunt The family each took turns to fly off the boatRecalling the story in a joint interview, Rod explained: ‘He was an absolute gentleman, he was band leader and bass player, and he kept her telephone [number] away from me.’He didn’t think I was in the right position because I had just got a divorce and didn’t know if I was coming or going, and he said I will give it to you when I think you are ready.’Rod joked: ‘I should of fired him, but I couldn’t!’Penny then began to well up with tears as she added: ‘Carmine had kept that telephone number away from him.’He said, “You are going to go a bit crazy over the summer and let your hair down, and Penny seems like a nice girl.”‘After hearing nothing from her future husband, she explained: ‘I really thought that was the last I would see of Rod. I remember processing those photos I took of Rod [at his concert] and thinking, what a lovely memory, and that was that.’