The Thamesmead Three spent Saturday night in Wormwood Scrubs Prison, along with 21 other 'jail birds' to raise money for Cancer Research UK.
"It was fun, scary...definitely an experience!", said Julia.
"Before being ushered to the gym, we were told not to look up, not to talk and to walk as fast as we could so not to bring attention to ourselves, but of course some prisoners spotted us and started shouting (remember there is more than 1200 male inmates and there were 24 of us walking under their windows - 19 of which were women! One inmate even shouted out his mobile number!)
"When we arrived at the gym hall, we were made to form an orderly queue before shouting out our number in line. For every person who got it wrong or didn't shout loud enough, we were told to do press ups.
"We were then ordered to jog around the gym hall, before collecting our 'prison package', which consisted of a cup, cutlery and prison uniform (grey jogging bottoms and a jumper) before playing a ball game and eating a typical prison dinner of rice and chilli, an apple and a dessert.
"At around 9pm when all the inmates were locked up, we were taken on a tour of the prison. We walked along all the wings and were also shown a strip cell. It was tiny - there is no room to swing a cat and yet it is the same size as a normal prison cell which consists of bunk beds, a table, a chest of draws and two inmates!
"Although prisoners are in there for a reason, the sheer claustrophobia of it all really made us wonder how they survive."
The Thamesmead Three have raised more than £1000 for Cancer Research UK, all 24 participants of the sleepover have so far managed to raise just under £10,000, which is fantastic, but they would still love to raise more.
A message from The Thamesmead Three: "Thank you to all those who have already donated. If you haven't yet donated but you would like to, click here."
"Remember, every penny, every pound counts!
"Please tell all your family, friends and colleagues about this page.
"Together we will beat Cancer."