Desperate to lure their son away from London and the drugs culture, the Civils offered to buy Blake a house near them, but he declined. They simply hoped he would grow out of it, meet a nice girl and settle down.

"When we first met Amy, she was very friendly and talkative, but she and Blake were very clingy with one another in a way that went beyond just being tactile.

"There was something a bit desperate-about the way they wouldn't let one another go, even in our company," says Georgette.

"When they first came to see us, they stayed the night then went back to London the next morning and that was the last we saw of them together until April this year, so we assumed, wrongly, that the relationship couldn't have been that serious.

"When they visited again in April, Giles and I booked a table at a restaurant in Newark, but when Amy and Blake arrived, they were shockingly different.

"Both looked in desperate need of a shower. Blake was tired and edgy while Amy seemed dreadfully emaciated and docile.

"It was a shock and we didn't know what was going on.

"At the restaurant, the pair were going backwards and forwards to the toilets and we suspected they must be taking drugs.

"Back home, we confronted them, but they denied drug-taking and said they were simply exhausted.

"Giles and I made it very clear that we would not tolerate any drugs being brought into our house.

"Blake and Amy continued in their denials, but they were very erratic and emotional, sitting huddled at our kitchen table, virtually in tears at one point and yet unable to articulate why.

"We were very anxious about their physical and emotional state."

The following month, Amy and Blake married - seemingly on a whim - while on holiday in Miami, in a ￡60 ceremony, followed by burger and chips and a 48-hour lock-in at a hotel. No parents were present.

Georgette continues: "Blake called us and said: 'Mum, congratulate me, I'm married. Would you like to speak to my wife?'

"I spoke to Amy and they both sounded so happy. When they came home they e-mailed us photos of the day they got married, and of them speeding around Miami on a boat. But I can't pretend that it was what I had hoped for for my son."

Amy's divorced parents Mitch, a cab driver from Kent, and Janis, a pharmacist, were equally upset.

Janis, 52, has said: "I think they were probably both so out of it that when he said 'Let's do it', she said 'OK then'."