Ed Miliband revealed he was with his mother when he first read the Daily Mail article that accused his father of "hating Britain."
He said he took exception to the tone of the article, the fact that a personal boundary had been crossed, and said he was speaking out "as a son" more than a politician to defend his father's name, and to protect his family. Speaking on BBC Breakfast, he said:
There has to be boundaries - and that is why I am standing up for my father, as a son. We, as a family are used to a lot, I think. But we think this went over the line. I was with my mum when I read it, and it is about my family, and where boundaries lie.
It is an usual thing that has happened, me speaking out, but I felt I had to speak out to protect his good name now
When it comes to my dad, there has to be some boundaries. When it comes to the election, it has to be about the issues, not about smears.
Both the Editor and owner of the Mail on Sunday have apologised for a reporter intruding on a private memorial for Ed Miliband's uncle.
Ed Miliband has written to the Daily Mail's chairman Lord Rothermere to complain about a reporter attending his uncle's memorial service.
The PCC said it had received 384 complaints by 4pm on Wednesday relating to Daily Mail articles about Ed Miliband's father.