Media playback is unsupported on your device Media caption Rolf Harris arrives at court flanked by his wife and daughter

Rolf Harris groomed and molested a friend of his daughter from the age of 13 onwards, a court has heard.

The children's entertainer denies 12 counts of indecently assaulting her and three other girls from 1968-86.

The court heard she used alcohol to cope from the age of 14 and was abused by Mr Harris until she was 29.

The prosecution told Southwark Crown Court Mr Harris, 84, was a "Jekyll and Hyde" character whose fame and reputation made him "untouchable".

His alleged victims were aged between seven or eight and 19 when the offences are said to have taken place.

Seven of the 12 counts are alleged to have been carried out on one victim - his daughter's friend - who lived near the Harris family in south London in the 1960s.

Image copyright Elizabeth Cook Image caption Sasha Wass QC, prosecuting, said there was a "side" of Mr Harris that was attracted to young girls

The court was read a letter Mr Harris is said to have written to the victim's father in 1997 asking for his forgiveness.

Concealed behind this charming and amicable children's entertainer lay a man who exploited the very children who were drawn to him Sasha Wass QC, Prosecuting

He was said to have written that the woman had confronted him about the alleged abuse.

"[She] told me she had been terrified of me," he is said to have written. "I said why didn't you just say no? She said to me: 'How could I say no to the great television star Rolf Harris?'"

The letter says: "I fondly imagined that everything that had taken place had progressed from a feeling of love and friendship - there was no rape, no physical forcing, brutality or beating that took place."

It continues: "When I see the misery I have caused [the alleged victim] I am sickened by myself. You can't go back and change things that you have done in this life - I wish to God I could."

"I know that what I did was wrong but we are, all of us, fallible and oh how I deluded myself. Please forgive me, love Rolf."

Prosecuting, Sasha Wass QC said the girl had been groomed like "a young puppy who had been trained to obey".

The court heard how the girl was abused while on holiday with the family as well as in her home and his.

Ms Wass said the assaults continued "when the opportunity arose" and that by the time she was 14 the girl was relying on alcohol to cope.

The jury was shown a school report which said the alleged victim had become "prone to tears and has been weeping about private/home matters".

Image copyright Getty Images Image caption Mr Harris and his family were greeted by photographers as they arrived at court

Ms Wass said that, on arrest, Mr Harris "categorically" denied having sexual contact with the girl while she was under 16, and said his letter to her father expressed regret because they had an affair later and he was a "married man".

She added: "The prosecution does not, for a minute, suggest that there is not a good, talented and kind side to Mr Harris.

"But concealed behind this charming and amicable children's entertainer lay a man who exploited the very children who were drawn to him."

She added there was "a side of him which is sexually attracted to children and under-age girls".

'Fame and reputation'

She told the jury "part of the excitement" for Mr Harris was touching "children and women alike in quite brazen circumstances".

Telling the jury about other alleged victims, Ms Wass said one was seven or eight years old when she queued to get an autograph from Mr Harris at a community centre in Portsmouth.

She said he signed an autograph for her then touched her inappropriately, leaving her "in shock".

In other alleged incidents, she said Mr Harris "started rubbing himself" against a 15-year-old girl at a pub in London, and touched a 24-year-old makeup artist in Australia, both in 1986.

Completing her opening statement, she said the evidence showed a "persistent pattern of sexual offending" and demonstrated Mr Harris "had a tendency to touch up females as if he was entitled".

Ms Wass said his fame meant that "no-one suspected or challenged his behaviour".

"Mr Harris was too famous, too powerful and his reputation made him untouchable," she added.

He arrived at court accompanied by his daughter Bindi, and his wife, Alwen Hughes.

He entered a not guilty plea at a hearing in January.

The Australian found fame in 1953 on BBC children's TV, a year after arriving in the UK, and has remained a well-known entertainer, musician and artist since then.

He had success with novelty pop hits and children's TV and variety shows as well as series about animals and art, and he painted a portrait of the Queen in 2005.