She said the early morning shifts on Sky's Good Morning Sports Fans left her so exhausted she was forced to quit. "I was getting up every day at 3am and going to work," she told Fabulous magazine.
"Oscar (her five year-old) had just started school. I could do some pickups, but couldn't take him to school, and that really bothered me.
"On top of that I was just so tired. By 4pm I became a monster. I'd feed the kids and then I'd be shouting at them at bath time because I didn't have any patience.
I'd apologise to Oscar for being bad-tempered and try to make him understand that it was because I was tired from work.
"After six months I realised I didn't want that. I love my job, but I also love my kids and I love my husband. I want to be a good wife and mother, so I explained how I was feeling."
Thankfully Kirsty's bosses at Sky were sympathetic and they moved her to afternoons.
"Everyone was amazing and I ended up doing the news later in the day, which I love and I'm so much happier," said Kirsty, 36.
"I do all the school runs and pickup on Friday, I leave the house in the afternoon and get back around 8pm, which works much better.
"I'd rather be happy in all aspects of my life than have just one thing going well and everything else falling apart."
Kirsty is looking forward to covering the London Olympics in a month's time in her new role at Sky Sports News, since the working hours mean a far happier home life where she's wife to former England rugby player Paul Sampson and mum to Oscar, five, and two-year-old Jude.
Were your bosses this flexible about juggling work and family, or did you just have to like it or lump it?