When I was asked to be the main mover of the amendment, I rang Mark and we talked through what the consequences might be, particularly in terms of media attention. The fact that Mark has never hidden his homosexuality meant that it was bound to come into it. Interviewers were going to ask me how I would feel if my own son were gay, and I was going to say "Well, my son is gay."
I knew that as soon as I was open about it, they'd want to talk to him, too. So it was a case of, let's say we are fine by that, and do it together.
It's impossible to be closer to Mark than I am already, but this has been an exciting period of shared experience.
Few mothers get the opportunity to do something that affects their children like this. It's been good to do this with him, when he obviously must have gone through pain about his sexuality.
Until he was in his twenties he tried to conform to what was all around him - heterosexuality - and he knew that not to conform was going to be difficult.
Parents don't want their children to go through pain of any kind, and what is more personal than your own sexuality? Not only are you suffering by discovering that you are gay, knowing that society discriminates; you have the added burden that you are a criminal at such a young age
In the last few weeks I've become aware that if at some young age people felt like criminals, it stays with them all their lives. I felt incredibly privileged to lead last Monday's motion. My politics is about equality and human rights, and so it was the natural progression to take.
Also, as a nurse for 25 years I've worked with heterosexuals and homosexuals, so I know the complexities of families and the difficulties that people have with not being able to be themselves, It's so important to be yourself.
This issue has always been close to my heart , but I definitely have a greater understanding of it through Mark.
I only really knew I was the right person to move the amendment when I got up to speak on Monday night, looked at the house and the opposing benches and started my speech.
It was very emotional, especially as I knew Mark was there, and I'm new to the House.
I thought, a mother, a nurse, the mother of a gay son, a woman, an older woman and an older straight woman is bringing this in, and rightly so.
Above all, though, I was speaking as a mother.
Ann approached me to say that she'd been asked to support this particular cause and how did I feel about it? I said I'd be proud if she did. She warned me that it could have an impact on me because the press and media have already focused on us and our story and the scrutiny would be even closer this time. Admittedly, it was somewhat overwhelming to find my picture on the front cover of much of the gay press, particularly since I live in Soho. But it's a good cause, and we were hoping that by showing a mother and son campaigning together on this issue, it would get the message across.
People wouldn't describe me as shy, but that particular type of attention can be somewhat intrusive. I don't think anyone who's never received any media attention could prepare themselves for it.
I've never felt more like the stereotypical gay man who's conscious of how he looks than when I saw my photograph in a paper and thought, goodness, is that me? That came as a bit of a shock - and I've joined a gym since. I've never lied to my colleagues, but equally I don't tend to say: "How do you do, my name's Mark Fox and I'm gay." To some people it may be obvious and to others not. So the whole experience felt a bit like coming out again. I thought I was done with all that, years ago. Still, I have no regrets whatsoever.
I get quite a bit of ribbing from close friends and colleagues about it. "Which front cover are you on this week?"
Even more overwhelming is that people I've never met before have come up and said that they think it's incredibly courageous to put yourself in the public arena for this particular issue. Frankly I'd never thought of it in that way and I still don't think it's particularly courageous. You live life from moment to moment. This came up as an issue for Ann, I was happy to support it and suddenly there were cameras in front of us.
It was indescribable watching Ann give the speech. You do normal things such as have breakfast or travel in the car with your parents, so it's amazing to find yourself in the public gallery of the House of Commons watching your mother stand up and open a debate to move a clause to equalise the age of consent. I was extraordinarily proud and excited. It was all like a dream, a play or a film.
After the vote had been announced, I went to a party organised by Stonewall for all the campaign workers and helpers . It was quite a shock to go to a night-club I'd been to before and see my mother's face magnified to a height of 15ft, delivering a speech to the House of Commons on a massive screen in front of 3,000 gyrating, mainly gay, young men and women.
Even with Ann's extensive knowledge and background in the subject, she rightly consulted widely on the contents of the speech. I helped out and there were certain areas where I felt that things needed more focus or stress than others, which is perhaps a perspective that only someone who's had the experience of an unequal age of consent can give. She doesn't always listen to my opinions though.
I've seen her more than usual because of the campaign but I haven't really spent more time with her because there's usually a journalist there, or we're in a group of 200 people. It didn't matter, though, because we're lucky in that we find it easy to socialise with each other, unlike some parents and children.
Interview by Rebecca Cripps