Sheridan Smith glowed with pride as she spoke about her baby son on Tuesday's episode of This Morning.The blonde beauty admitted that she wanted to be "the best mum in the world" after opening up about her struggles with her mental health, which she is fronting a documentary exploring the issue of.The 39 year old told hosts Holly Willoughby and Phillip Schofield: "I think when you've had mental health issues in the past you're worried they're going to appear again in pregnancy.