"[Barnett suffered a herniated disc four months after giving birth] I'd had a c-section and two and a half years of IVF and heavy steroids. I wasn't physically good going into the pregnancy or coming out of it. It was an unholy situation and one day I picked up my daughter and it went. It was agony trying to breastfeed, do the school run with my older son, hold my baby daughter through gritted teeth and put the car seat in. So I've also been doing months of physio, exercise and Pilates."