The two men, along with Daniel Whitworth and Jack Taylor, were all killed by Port with overdoses of GHB in the space of a year.
Met officers who initially investigated the deaths - and failed to spot that a serial killer was on the loose - are now under scrutiny at an inquest into the death of the four victims.
Mr Kovari’s older brother Adam, in a statement to the hearing, said he blames the police for not catching Port sooner.
“He made a mistake of trusting people too much,” he said of his “exceptional and ambitious” sibling who “would be leading an amazing life today if he had a chance”.
“This cost him life, but it should not have. In my opinion, had the police done their job, my brother could still be here with us today.”
Mr Kovari said his brother was a “very smart, talented, kind person with passion for drawing and languages”.
“He was the most talented of all of us in the family when it came to artistic expression,” he said.
“After I left our hometown to go to university, we would grow apart even more. We would only talk occasionally, but I always knew we still cared for each other very much and I believed that once we both build our adult lives, we will find a way to be best friends again.
“This never happened and there has not been a day since he is gone that I would not regret this. I regret not being a better brother growing up, I thought we still had plenty of time ahead of us. I could not have been more wrong.”
Sarah Sak, mother of Anthony Walgate, told the inquest about his naughty nature as a child, and said he was a quiet pupil at school.
“He only changed when he went to college, I could see and feel his confidence growing daily,” she said.
“He developed a very dry wit and really made me laugh. It was usually at the most inappropriate times.
“Just before Anthony was 18, he told his dad and I that he had an interview at a uni in London. I begged him not to go and to stay in Yorkshire, somewhere local. He replied that he would be famous one day with his name in lights. He loved fashion and it was the only place to achieve this.
“The longer Anthony was in London, I could see the cygnet becoming the swan, he seemed to blossom and find who he really was, and he could dress and act however he wanted. He loved London, his friends and the life he had there.”
She added: “For the last seven years, every time I talk about my son I call him Anthony. I never ever called him that, it was always Ant, but I still cannot bring myself to call him that, as it is so personal and to me it would mean my boy is really gone forever. I now realise forever is a long, long time.”
Daniel Whitworth’s stepmother Mandy read a statement on behalf of her husband Adam, saying Daniel “couldn’t wait to get out into the big world of catering” after leaving college.
Mr Whitworth said his son “struggled with his sexuality” but came out to his family after meeting boyfriend Ricky.
“Daniel had all his priorities in the right place. Nobody is perfect, but my son worked so hard, his circle of friends was small and consisted of mostly Ricky and his family, Mandy, myself and Grandma.”
He added: “I don’t understand, or know why he decided to go on Grindr, but we waited a while to find that out, we waited a while to be told his life had been snuffed out at the hands of someone else and not his own.
“At the point of being informed of his death, we were not asked to identify him and this would have been our way of believing what we had been told.
“I miss him enormously and I will never get over is loss. Rest easy, my son, Daniel.”
Mr Whitworth’s grandmother Barbara called him “a total joy”.
“Daniel was my pride and joy and I can’t even begin to tell you how much I miss him”, she said. “He had his whole life in front of him and it seems so unfair that he was taken from us at such a young age.”
Jack Taylor’s sisters Donna and Jenny told the inquest his family and friends hold a memorial each year, and they still set a place for their brother at the Christmas table.
“He literally had his whole life ahead of him and he loved life so much and appreciated everything. If only we didn’t have to talk about him in the past tense,” they said.
“There is no amount of words to even be able to explain how much he is missed or to describe the pain we have to go through on a day-to-day basis.
“Our whole world’s been shattered into pieces, our family has a big hole missing and we are all so broken without him. We love him so very much, we always have and we always will.
“We miss him always and there’s not a day that he doesn’t go through any of thoughts. He was the centre of our world. We miss his laugh, his humour, his personality, his love for his family and everything about him.
“We will never stop fighting for you Jack and we all love and miss you more and more every day.”
Port killed his four victims during a spree of drugging and raping young men at his home in Barking between 2012 and 2015.