A mum got revenge on her 11-year-old son after he pranked her by pulling her chair away in public - by secretly removing the slats from his bunk bed. Abigayle Gibbs, 30, was the victim of her son Billy's mischievous antics when he pulled her chair out from underneath her at a family birthday party. But she got revenge by removing the base of his bed - putting the mattress back - and setting up a camera to catch him taking a tumble. The stay-at-home mum from Bovingdon, Hertfordshire, said Billy has been pranking her all his life. "He always jokingly torments me," she said. "Sometimes it's an egg on the head, sometimes he puts biscuits in my Red Bull or just makes me jump in the kitchen." Abigayle said she was 'shocked' when Billy pulled her chair out. "I didn’t realise what had happened until I was on the floor and my sister started filming," she said. Abigayle hatched a plan about how to get Billy back. "He went upstairs and asked why there was a camera in his room," she said. "I told him it was because he was on his phone too much and I wanted to monitor it. "He thought that was stupid. "When he jumped on his bed and fell through I heard him shout 'so that's what the camera was for!'" Billy has already told his mum that he plans to get her back, and she's "dreading" it.