The nephew of serial killer Rose West has been jailed for 18 years after he was convicted of drugging and raping a 12-year-old girl.

Steven Letts, 39, abducted and had sex with the child after they met in the street and she asked him for a cigarette.

Letts, who was found guilty of kidnapping and rape last week, responded by offering her a joint, then took her home and plied her with cocaine, cannabis and vodka after their encounter in Gloucester city centre on 6 March this year, the trial heard.

The girl, who lives in care, had been in the company of her support worker, who told Gloucester Crown Court she had warned Letts that she was underage.

Letts, of Barton Street, Gloucester, pleaded not guilty to abducting the girl on 6 March and raping her in his flat between March 6 and 8, though he was found guilty on both counts.

The trial heard Letts and the girl went back to his flat to drink apple vodka and smoke cannabis. He also gave her cocaine to smoke through a pipe.

The rape came to light when the girl asked a social worker “how long it’d take to find out if you are pregnant”.

The court heard Letts kissed the girl in his kitchen and when she became tired she went to sleep under a blanket in Letts’ bed. He climbed in and began “cuddling” the child before initiating sex.

The ordeal lasted 30 minutes and prosecutor Sarah Regan said the victim wanted Letts to stop but felt guilty because he had given her alcohol and drugs.

When Letts was later arrested, police found DNA matching the girl inside his underwear.

Letts claimed he believed the girl was 16 when they met, though the girl told him she was 15.

Summing up, Judge Jamie Tabor QC read the girl’s statement about events at Letts’ flat.

“He kissed me and I said I can’t do this because I’m only 15,” it said.

“He told me sad stories like a couple of months ago he tried to strangle himself. I think he said that so that I’d feel bad and kiss him.

“I did tell him I was 15 [instead of 12] because I thought I had more of a chance of getting drink and drugs.”

The panel returned a unanimous verdict with all twelve jurors finding Letts guilty of both charges.

Letts claimed he was a “good Samaritan” who had helped the girl when she was upset, and denied having sex with her.

Police were tipped off by the support worker but the girl did not divulge the details of what had happened immediately. The following day the child told a support worker that Letts did have sex with her.

When police quizzed her about it, she said she had not told them because she did not want to get him into trouble.

Letts is the estranged son of Rose West’s younger brother Graham. Rose West was born Rosemary Letts in Northam in Devon to William Letts and Daisy Fuller.

Rose is now an inmate at HMP Low Newton, Brasside, Durham, after being convicted of ten murders in 1995. Fred West died in prison in 1995.