Nicola Roberts: 'Twitter highlights bullying problem'
Singer Nicola Roberts has said Twitter highlights the severity of the bullying problem, which is "out of control" in schools.
She wants to talk to education secretary Michael Gove about the issue.
She told Andrew Neil how she was bullied even after finding fame, and the issue was explored in the song Sticks and Stones on her new solo album.
Michael Portillo and Alan Johnson offered a view on bullying among politicians and famous people.