The conviction of a woman for sexually assaulting a baby and allowing her boyfriend to take photographs of the abuse has brought an end to “one of the most sickening paedophile rings this country has seen”, prosecutors have said.

Tracy Dawber, 44, was the fourth woman to be convicted of abuse and pornography offences relating to “evil” paedophile Colin Blanchard’s internet child abuse ring.

Ms Dawber, a community care worker, wept as a jury at Winchester Crown Court took just two hours to find her guilty of the assault, and of allowing Blanchard to take pictures of the abuse on his mobile phone.

She let IT consultant Mr Blanchard, 40, take photos at her home in Southport, Merseyside, in August 2008 as she assaulted the baby on her sofa. The pair then took photos of themselves on the same phone taking part in sex acts.

The case had parallels to other women Mr Blanchard met over the internet, including Vanessa George, who abused young children at a nursery in Plymouth, Devon, and Angela Allen, who also abused children to please Mr Blanchard.

Ms George and former prostitute Allen were sentenced at Bristol Crown Court earlier this year for a string of sexual assaults and making and distributing indecent images of children.

Mother-of-two George and single mother Allen, from Nottingham, carried out the offences with Mr Blanchard, from Smithy Bridge, near Rochdale, after they all met on Facebook. They were given indeterminate sentences and Mr Justice Royce has warned Ms Dawber that a lengthy custodial sentence is inevitable.

She is now likely to be sentenced in November alongside Mr Blanchard and another woman, Tracy Lyons, from Portsmouth, who has admitted her part in child abuse with Mr Blanchard.

Mr Blanchard previously admitted being involved in the assault, the jury was told, and he has also admitted his crimes in relation to the other women.

Ms Dawber was found guilty of one count of sexually assaulting a child and five counts of permitting indecent photographs of a child to be taken.

She was unusual in the group of women because she actually met Mr Blanchard and the pair had a year-long relationship. George, Allen, Ms Dawber and Lyons have never met.

Ms Dawber denied the charges but Mr Blanchard told the court she had taken the lead in the abuse, during the two-week retrial after a previous jury failed to reach a verdict.

She told the jury that she could not remember Mr Blanchard taking the photos and she was only checking for nappy rash and not abusing the baby.