Fellowes was joined by singer Lulu, actor Edward Fox and members of Rees' family who gathered at St Paul's Church in the Knightsbridge area of London to celebrate her life on Thursday (27Sep12).
The British star, best known for her role in 1970s U.K. TV series Poldark, lost her battle with pancreatic cancer in July (12) at the age of 63.
Fellowes told the congregation, "She was a fighter. Not for nothing was her nickname hand grenade. I have only had four real rows since I was grown up and two of them were with Angharad. We once emptied a restaurant, when the other patrons started to ask for their bills, or to be seated elsewhere to get away from the noise we were making.
"But, if her fierceness made her a frightening opponent, it was a wonderful quality to have on your side. Because, if there was one thing she was superb at, it was friendship, and not just sympathetic friendship but hard-working, useful, practical assistance."
He also praised Rees for balancing her career with family life, adding, "She was determined that it would be her children who took precedence. She was not prepared to pay the price of being a great actress if it meant that her family would have to pay it with her.
"She was anxious, I think, that she should not be defined, entirely, as the star of a popular series, as one half of a golden couple, as a mother and hostess, although she excelled in all of these."
The 74 year old rents a property in the British capital's exclusive Knightsbridge, but was not home during the festive season.
Police were called to the address over the holidays after squatters in a neighbouring building spotted a man allegedly attempting to gain access to the property through the front door.
Documentary maker Mark Guard, who is making a film about the squatters who have taken up residence in the up-market neighbourhood, says: "He (the alleged burglar) broke off some shoots from a bamboo plant, then he waited until the coast was clear and spent three or four minutes poking the bamboo through the letterbox. By this stage we'd already rung the police. They sealed off the square and searched with dogs for half an hour before they arrested a man."
Jarvis Ojofietimi, 31, has been charged with burglary and is due to appear at Isleworth Crown Court later this month (Jan10).
The stunner was recently exposed as a cocaine user in British tabloid The Sun and now she's revealing what she did to earn upto $22,500 (£15,000)-an-hour as a prostitute to millionaire businessmen.
She tells the publication, "This is the truth, warts and all. For a short while I sold my body for a lot of money. I am not proud of it... In the summer of 2004 I was drinking a bottle of vodka a night and using cocaine by day.
"The coke ran out, my cash card was rejected and my dealer was ringing up demanding payments. I knew I desperately needed money - now."
Anderton admits her first sexual encounter as a hooker lasted less than two minutes: "I felt a bit sick before my first time. But I told myself to get a grip. I got a taxi to a hotel in Knightsbridge, West London. I was shaking and sweating. I was dressed in a black Dolce and Gabbana suit, with six-inch Louboutin heels. I looked respectable, successful, normal.
"I went to this man's room. I had told the madam I didn't want to be with some horrible fat, old man. So when he opened the door I was relieved. He was a smart Arab, mid-30s and quite handsome. We shook hands. He seemed so lonely my nerves vanished and I felt sorry for this man.
"After about 40 minutes of talking, I decided to take charge and stood up and took my dress off. I pushed him back on the bed while he looked at me eagerly. I closed my eyes and quickly pulled down his underwear. I felt in control. It was over very quickly. He handed me the cash and I slipped out."
The model admits she was an instant big hit: "I actually giggled when she (the madam) asked if I fancied a trip to Florence. I thought, 'Italy doesn't sound too bad'. Suddenly I was on a plane, first class. I was taken to a beautiful hotel, where a porter showed me to my room.
"It was filled with chocolates, champagne, flowers. Laid out on the bed was expensive underwear with a note that read, 'Please put these on'."
The client was a British businessman she knew, and her money-making side venture almost came to a crashing halt.
She adds, "He said, 'Sophie, why is a nice girl like you doing something like this?' I couldn't answer. But the sex was amazing and the following morning I woke up and found a Christian Dior bag filled with £50 notes. I'd sold my body again and this was what it was worth."
Her days as a high-class hooker ended when she almost threw up during sex with a "leering" overweight businessman: "I felt sick. His face was sweaty and cheerful, like a cat who'd got the cream. For the first time, I felt like a piece of meat. He stripped, revealing a huge stomach. It was over in a minute. I left trembling and crying.
"I had slept with five men and made more than £50,000, which paid my drug debts and a deposit on a flat. Now I could escape."
The Charlie's Angels beauty, who previously dated Justin Timberlake and Matt Dillon, split from British model Paul Sculfor earlier this year (09).
And a string of Hollywood bachelors have been vying for her attention while she is in London, taking her out on secret dates.
Diaz was said to have enjoyed an evening with her Gangs of New York co-star DiCaprio earlier this month (Jul09) before heading out with Jude Law to party at the British capital's Boujis nightclub on Sunday (19Jul09).
A source tells Britain's The Sun newspaper, "Leo is back on the pull (single) after he split from his long term girlfriend Bar Refaeli. Cameron has been showing a lot of interest while he is in London filming. She was back at his rented apartment in Knightsbridge, West London, a couple of times last week after a series of secret dates. They were joking with friends that they played chess together.
"Jude and Cameron have been good friends since they filmed The Holiday together a few years ago. Now they are both single, things are a bit different between them. Jude has been flirting with her and she has been playing along.".