Claire, from Coventry, West Midlands, was just about to put the fresh Huggies nappy on her little girl when she spotted the piece of wood.
She told The Sun: "I had a closer look and realised it was like a stick, a big long piece of wood that was sharp at both ends. It looked like a toothpick. I was furious - it could have done some serious damage."
The horrified mum added that as Peyton is running around a lot, she often changed her standing up, but on this occasion she was lying down and so the splinter was spotted - Claire says that otherwise, she would have probably missed it.
She complained to the makers, Kimberley-Clark, who offered her a voucher for £20 by way of compensation, but the worried mum said she would not be buying Huggies again and wanted to make sure this kind of thing did not happen to other parents.
A Kimberley-Clark spokesperson said: "We have been in contact with Claire Swinburn following her discovery of an unidentified material in a Huggies nappy. As is standard procedure, we have asked for samples from her, and when we have them we will carry out a thorough investigation into what has happened. As a responsible manufacturer, the safety and well-being of our customers is a priority."
Yesterday it was needles in Turkey Drummers and now splinters in nappies!
Do stories like these make you extra vigilant with everything you give to or use on your kids?