It was Abi Webster (Sally Carman)’s birthday in Monday (September 29)’s Coronation Street, but the day ended in turmoil when sister-in-law Debbie Webster (Sue Devaney) finally uncovered Abi and Carl (Jonathan Howard)’s secret affair.

Debbie’s suspicions were roused when Abi dropped a key card from the Chariot Square Hotel on the floor in the Kabin, and she quickly reached the conclusion that Abi had been ‘visiting’ Carl.

At that point Carl covered up what had been going on by making out that Debbie was being irrational because of her dementia. This was a move that even Abi thought was a bit brutal.

Later, after some thefts had been reported at the hotel, Debbie was checking the CCTV footage and saw Abi making her way along the corridor where Carl’s room is. She had the proof she needed and headed straight off to confront her brother.

Carl had been entertaining James Bailey (Jason Callender) in his room and the fitness instructor had only left the room moments before Debbie stormed in.

She did find a condom wrapper on Carl’s floor, though, and assumed this was proof that Abi had been there. She told Carl she would check every bit of CCTV footage.

Cornered, he admitted he’d been having an affair with Abi which had only started after Kevin (Michael Le Vell) lied about still having cancer – which is technically if not morally true. He said he was serious about her.

Fuming, Debbie soon found Abi and said she knew all about her ‘mucky little affair’ with Carl. Abi subverted Carl’s version of events a bit by saying they’d fought their feelings for months before anything happened.

Then there was a tense showdown when Kevin and Jack (Kyran Bowes) returned. Was Debbie about to confirm to Kevin what he’d long suspected, that his wife was having an affair with his brother?

Debbie didn’t do that, but said that Abi should leave number 13 because she was playing Kevin for a fool. But even when he suggested that her dementia was clouding her thinking, she didn’t mention Carl’s name, not wanting to hurt him further.

A relieved Abi relayed this to Carl later, telling him that it was probably time they went public with their relationship. Despite earlier telling Debbie how serious he was about Abi, every time she suggests something that would make their relationship more public or permanent, he backs off, or looks like he has misgivings.

Basically he’s not as serious about her as she would like to think, and he’s obviously enjoying having both her and James on the go at the same time.

For Debbie, she’s been left in a really hard place. Carl spun her a story about how his mother had told him he would never amount to anything, so she didn’t want to reject him again.

At the same time she’s desperate for him not to ruin Kevin’s life and begged him to walk away from Abi – for her sake.

Later, Ronnie (Vinta Morgan) found her looking through family photos. There was one of her with her two brothers and Ronnie suggested she could get it framed.