Jack had a dramatic life since his birth, as in 2010 he was trapped alongside his mother in the Corner Shop following a tram crashing into it and was rescued. In 2015 he was kidnapped by his father's unstable girlfriend Jenny Bradley, and in 2018 lost his foot after developing sepsis.
Kevin had rejected the idea of bringing a child up with Molly, so Molly decided to give her marriage to Tyrone another try by telling him that he was the father. Molly went into labour on 6th September 2010 while Tyrone was out at work. Kevin's wife Sally realised that Molly was soon to give birth at home and had to deliver the baby herself. The baby was named after Jack Duckworth.
At Jack's christening, Kevin and Sally were named godparents. Kevin stole one of Jack's dummies in order to have a DNA test. He confronted Molly with the evidence that he was indeed Jack's father. Over the following weeks, Molly found the pressure of the deception too much and realised that she felt no love for Tyrone. On 6th December 2010, she left Tyrone, telling him that he wasn't Jack's father. On her way to the bus stop, Molly took Jack into the Corner Shop. While they were inside the shop, a tram derailed and crashed into the shop. Molly died but Jack was relatively unharmed.
At his mother's funeral, Jack's true parentage was revealed and a disgusted Tyrone gave Jack to Kevin to raise. Kevin took Jack into his family home at 4 Coronation Street, even though his marriage to Sally had ended. After Christmas 2010, Jack and his father moved into a flat near to the Street.
In September 2011, Kevin realised that he would need to apply for parental responsibility in order to change Jack's surname to "Webster" for his passport, and Tyrone's name was finally removed from the child's birth certificate in December of the same year.
Between 2012 and March 2013, Kevin and Jack lived at 13 Coronation Street, before moving back to No.4 to allow the Price family to move in temporarily following the Rovers' fire. They flew to Germany the following month to be with Kevin's father Bill who had recently suffered a massive heart attack and returned almost a year later on 21st March 2014.
In 2015 Jack began to bond with his father's new girlfriend Jenny Bradley. Jenny however, was obsessed with Jack due to the death of her young son a few years earlier and became too concerned for his safety. Jenny devised a plot to abduct Jack and move him in with her at a new flat. This was uncovered by Maddie Heath who attempted to alert Jack's sister Sophie but was killed after being caught in an explosion at the Builder's Yard during the Victoria Court fire.
During Maddie's funeral Jenny took Jack and left with him in a cab. She took him to an apartment in Hull where she planned to stay with him. Jenny wanted him to celebrate her deceased son's birthday with her, but Jack was more interested in seeing his dad. Jenny was upset by Jack's disinterest, so she called Rita Tanner and asked her to come and meet her. Jenny briefly contemplated jumping off a balcony with Jack, but changed her mind and returned Jack to Kevin and Sophie.
When Jenny returned in early 2016, Sophie instantly suspected that Jenny would try to abduct Jack again. Jack briefly went missing and was found with Jenny, therefore leading Kevin to suspect that she had once again tried to abduct him. However, he later found out that Jack had actually wandered off and Jenny was trying to return him home.
In May 2016, Jack was taken to Blackpool with Kevin and Tim Metcalfe. They were later joined by Sally Metcalfe and Sophie Webster as Sally wanted to save her marriage to Tim. During an argument in a cafe on The North Pier, Jack ran from the cafe and out into the path of an incoming tram. Jenny Bradley and Johnny Connor spotted him and Jenny grabbed Jack, rescuing him before the tram hit him. Sophie accused Jenny of following him again but later thanked her when she realised she was mistaken about Jenny's motives.
In July 2018, Jack was diagnosed with sepsis after cutting his knee playing football. What made matters worse, is that his body wasn't reacting with the antibiotics as well as the doctors had hoped he would. As a result, the doctors were forced to amputate Jack's foot and lower half of his leg in order for him to survive.
- Jack was originally played by twins Jaxon & Maddox Beswick from his birth in September 2010. Another set of twins, Alex & Ellis, played the character alongside the Beswick twins in November and December 2010. Jaxon left the role in December 2014, while Maddox continued to portray the character until February 2016. In May 2016, the role was taken over by Kyran Bowes.
- Jack was absent from the programme from February 2013 to March 2014 and again from April to September 2014. His first absence was due to Michael Le Vell, who plays his on-screen father Kevin, being suspended on criminal charges which he was eventually cleared of. His second absence was when Le Vell took time off the show to deal with drug and alcohol problems.