"DA, watch you don't rip your trousers", Ian Paisley jnr shouts as his father stomps up a grassy bank like a young stallion and leaps the railings.
It's the Balmoral Show, Northern Ireland's premier agricultural event, and the Rev Ian Paisley (70) is clearly getting carried away. He jumps over ploughs and tractors, gallops by combine harvesters, and shakes hands with everyone.
These are his people. The solid, Ulster farming folk who, election after election, have never let him down. Here, he's not a figure to be hated or feared. He's simply "Big Ian" who states his views on the Union in no uncertain terms and looks after his people with fierce loyalty. "I'm fighting your case on BSE at home and abroad," he says. "And I'm still eating beef. Nothing I like better than a big, juicy steak."
He is mobbed by admirers. Ear ringed teenagers asking for autographs. Gnarled farmers commending his television performances. Respectable matrons in their Sunday best asking him to pose for a photo.
"Give me the kiss of life on May 30th, ladies," he says with a big grin. They dissolve into gig ales. Ian Paisley jnr plays a support role. He is friendly and outgoing but most definitely dwarfed.
Both men are standing in North Antrim. It's the DUP leader's 17th election and his son's first. Ian Paisley jnr (29) has worked as his father's assistant since graduating from Queen's University with a history degree. "I've been licking envelopes and pasting up posters since I was knee high. I get a great buzz from elections. My twin, Kyle, and I used to be at my father's feet at political rallies when we children.
It was a normal, happy childhood, Ian jnr says, contrary to what many friends imagined. "They said it must be terrible being Ian Paisley's son. They thought I was beaten every night if I did wrong."
Dr Paisley was a "loving, warm father". Discipline was strict but not crushing - an occasional whack with a hairbrush for misbehaving."
Ian jnr says that at home his father is a very different man from his public persona. My memories are of us all crowding round the television with my da on Saturday morning with liquorice allsorts and wine gums," he says.
"Ian Paisley had to be a hardened politician in public back then. DUP members were spat at on the streets. He was hated. His opponents tried to crush him or buy him off. They were able to do neither. He built the party into a real alternative to Ulster Unionism."
The Paisley children were given the space to develop their personalities, he says. "None of us ever really rebelled against my da because things weren't rammed down our throats."
Ian jnr is a practising Free Presbyterian but is strongly left of centre on social and economic issues. Strangely, for a Protestant fundamentalist, he believes that there should be a clean break between church and State with no clerical influence, for instance, in State schools.
On the Union, Ian jnr's views are as uncompromising as his father's. He has ambitions to become an MP but stresses that he would not be a carbon copy of "the Doe".
"We believe in the same things but we put them across differently. I am not a fire brand orator. I am very much my own man, with my own attitudes and ideas.
"I don't mind if people's first reaction to me is, `I know your da'. Northern Ireland is a small place and Ian Paisley is a huge personality. But I want people to relate to me as a person in my town right as well."
Ian snr says he is very proud of his son. "He is a great help to me. He has still a long way to go yet but he will learn from his mistakes."
The election means a heavy schedule for father and son. Campaign meetings begin as early as 7 a.m. and it's usually midnight before the DUP calls it a day. "Ian's doing well," says his father, "but I don't know if he'll be as fit as me when he's 70."
Suddenly, the DUP leader spots Wee Annie, a prize winning filly, and takes her for a trot around the show. "I could ride to victory in this election," he bellows, drawing a comparison with Prince William of Orange.
Dr Paisley marches on, leading his son and the canvass team with vigour. They meet a party supporter who introduces himself as "Robert jnr". "I know how you feel," says Ian jnr with a knowing smile and a shake of the head.