A man whose girlfriend ran off with his stepfather and gave birth to a baby nearly four years ago has spoken of his delight after DNA tests proved the baby is actually his. Love rat Stan Crowther, 47, and Rachel Delaney, 18 at the time, set up home together and Rachel then gave birth to a baby daughter,  whom Stan believed was his. But recent bombshell DNA tests showed that the baby, living in Chorley, Lancashire, actually belongs to her former partner, and Stan's former stepson, Ashley Mercer, 27. Ashley Mercer (left, pictured in 2010) was heartbroken when his girlfriend Rachel Delaney began an affair with his stepfather Stan Crowther (both pictured right). Rachel had a baby shortly after moving in with Stan and recent DNA tests have proved that the child is in fact Ashley's . Stan Crowther, 47, with the baby daughter he believed was his until recent DNA tests proved otherwise . The affair between Stan and Rachel shattered Ashley and his mother, Mandy, who has astonishingly now forgiven Stan for the affair. Mandy, 47, who has now found new love with partner Andy Barker, says: 'It's been a rollercoaster few years. It might sound funny, but I'm happier now than I've ever been before. 'I have forgiven Stan. We're friends again. And my son has moved on with his life too and has a new daughter to be proud of.' Both men were left reeling from results of DNA tests which show that Ashley - and not Stan - is the father of Rachel's daughter. Ashley says: 'I feel very bitter towards Stan. I trusted him, I used to call him dad and I can't forgive him like my mum has. 'I'm buzzing to find out I am the baby's dad - and Stan isn't.' Love rat Stan with Ashley's mother Mandy Rourke, 47, whom he was married to for ten years . Ashley Mercer was in a relationship with Rachel's sister Kelly before he met Rachel, and the pair have a son, pictured, now seven . Kelly Delaney, Rachel's sister, with her son with Ashley . Ashley has five children with five different women - including a son with Rachel's sister Kelly. He started seeing Kelly when he was 19, and their son is now seven. But they split when he was three years old. Ashley was single for just three months before he moved on from Kelly to her half-sister, Rachel, in 2010. Rachel, then 16, began working at the family firm: a Lancashire tattoo parlour. Ashley says: 'Rachel was very similar to her sister, but she was naughty. We had a lot of fun together.' Rachel soon became part of the family and Ashley's mother, Mandy, grew fond of her. But Ashley began to suspect an affair between Rachel and his stepfather Stan, confiding in Mandy, who at first dismissed the idea as outrageous. Rachel and Stan when they first got together: Their relationship fizzled out 18 months later and DNA tests have now proved that Ashley is the baby's biological father . Stan and Rachel  set up home together, and Rachel then gave birth to a baby daughter, whom Stan believed was his . Ashley says: 'I saw them in the car together, play fighting, but then they were getting too cosy. 'I was sickened. Stan and my mum had been married for ten years and I called him dad. He was my father figure.' Horrified by her son's claims, Mandy turned detective and began checking the mobile phone belonging to the tattoo parlour - which Rachel took home with her each night. She says: 'The account was in my name and I checked her bill and Stan's. Stan was sending loads of texts. 'I spoke to Stan and he became very defensive and shifty and I knew, instantly, there was something going on.' She confronted Rachel and found intimate text messages between her and Stan. Horrified, she threw Stan out and Ashley finished with Rachel. Mandy, 47, has found new love with partner, Andy Barker . Mandy (pictured with new partner Andy) says: 'I was furious that Stan had betrayed me. But it hurt even more that he had betrayed Ashley' Mandy says: 'Ashley was gutted. He hadn't wanted to believe it. He stopped eating and he started drinking heavily. 'He'd had a stammer as a kid, but it came back much worse. I was really worried about him. 'I was furious that Stan had betrayed me. But it hurt even more that he had betrayed Ashley.' Rachel then announced she was pregnant. Mandy says: 'At first she said it was Ashley's baby, then she said it was Stan's. It was disgusting. Poor Ashley was totally up the wall.' Rachel eventually announced that the baby, born in March 2011, was Stan's, and the couple set up home together. It was the last straw for Mandy, who filed for divorce. Mandy (pictured with younger son Josh, now 19) turned detective and began checking the mobile phone belonging to the tattoo parlour, which she ran with Stan . Mandy (left) says: 'I spoke to Stan and he became very defensive and shifty and I knew, instantly, there was something going on'; Right: Rachel pictured in 2010 . But Rachel and Stan's relationship fizzled out 18 months later and DNA tests have now proved that Ashley is the baby's biological father. Ashley is now is a new relationship with partner, Deanne Parry. The couple are planning to get engaged and he has contact with Rachel's daughter. Perhaps most surprising of all, Stan and Mandy are friends again, though she vows she will never forgive Rachel. Mandy says: 'There's no relationship there, but Stan and I are friends. For a long time, I was angry and bitter. But life is too short for that.' Rachel says: 'I wanted the baby to be Stan's. But deep down, I knew there was a chance Ashley was the dad. 'I didn't want my little girl going to school and not knowing who her dad was. I paid for the DNA test. Ashley didn't pay a penny. I am not sure whether I will put his name on the birth certificate. He needs to step up as a dad.' Stan has since moved away to start a new life and says: 'I am heartbroken. I thought that little girl was mine and the DNA results were devastating. I don't see Rachel any more. 'I regret the way I treated Mandy, and we are friends again now. I wish things had happened differently but I just have to get on and start again.'
Ashley Mercer was 22 when he discovered his girlfriend Rachel Delaney, 18, was having an affair with his stepfather Stan Crowther, 43 . Stan had been married to Ashley's mother Mandy Rourke for ten years . Stan and Rachel moved in together and shortly after Rachel, from Chorley, Lancashire, gave birth to a baby girl . Stan assumed the baby to be his but DNA tests have since revealed Ashley  is the four-year-old girl's real father . Ashley's mother Mandy Rourke has now forgiven her ex-husband . Stan and Rachel are no longer together .