Ed Miliband was advised by his young son to include "dinosaurs that eat people" in his conference speech, he revealed today.
In a jokey start to his unscripted address, he told party activists that preparing for the keynote address could be "a bit of a trial".
To escape the constant tips from advisers and other politicians, he said, he had sought refuge in vain in a family trip to the park.
"The other day, this is an absolutely true story, I decided that to get away from it all, the speech writing and all of that, I would go for a walk with my three-year-old son Daniel," he said.
"It was an absolutely gorgeous late summer day.
"Here is the first thing he said: 'Daddy, I can help you with your speech'. I was like, not you as well... he is a Miliband, after all.
"And he said to me 'Daddy, you can't do it on your own.'. This is absolutely true, and I said 'Well, that's a good Labour insight: you can't do it on your own. Daniel, what do you want in your speech?'.
"He said 'I want dinosaurs, I want flying dinosaurs, I want dinosaurs that eat people, Daddy'."
But Mr Miliband - in a reference to his speech last year in which he took a pop at "predator" capitalists - added: "I said 'No, Daniel, we tried predators last year'."
He said that of all the names he had been called since becoming leader, his favourite was "when Mitt Romney came to Britain and called me 'Mr Leader"'.
"I think it has a certain ring to it - it's halfway to North Korea," he said.
Hailing his election to the leadership in the same hall two years ago, he added: "I'm older - I feel a lot older actually. I hope I am a bit wiser. But I am prouder than ever to be the leader of the Labour Party."
