The mother of two teenage daughters who committed suicide has called for the controversial ask.fm website to be shut down.
Lorraine Gallagher - whose children Erin and Shannon took their own lives last year - told Channel 4 News she does not want to see more young people kill themselves after being bullied on the site.
Last week the father of Hannah Smith, 14, who was found dead in her bedroom on Friday August 2, said she had been "cyberbullied" on ask.fm.
The question-and-answer site allows users to send messages to one another without their identity being disclosed
Dave Smith, 45, called on David Cameron to put regulations in place on such social networking websites to try to prevent another tragedy.
Ms Gallagher's daughter Erin was 13 when she hanged herself in the family home last October. She had been bullied at school, her mother said, and in a note in which Erin said she could not take it any more, she mentioned ask.fm.
A few months after Erin died, her 15-year-old sister Shannon committed suicide.
Ms Gallagher told Channel 4 News: "I would love to see it shut down. I don't want to go and see another child has killed themselves because of bullying on ask.fm."
She also said she felt let down by the authorities who should have helped her protect her daughters.
"I just want someone to hold their hands up and say 'we got it wrong'," she said.
But Karen Ingala Smith, who runs an anti-rape and anti-bullying charity nia, said that she did not think closing the website was the answer, but tackling attitudes.
"One of the problem’s with sites like Ask.FM is that if it wasn’t this forum, it would be another one; so the thing we need to do is work with young people to change their attitudes and understanding," she told HuffPost UK
"Not only has this the potential to change the way that young people relate to each other here and now, it can help them develop healthy relationships as they become adults. Working with children and young people around healthy relationships and sex education is key to ending violence against women and girls.
“We’ve been running a programme of workshops in schools focusing on sexual violence and sexual bullying.
"One of the things that is immediately obvious is that many young people as desperate for safe spaces to learn more about healthy relationships and these are currently rarely provided.
"They haven’t been given the support to look at what affects their attitudes around sex and relationships and how what they do and say can have an impact on others."