BRENDAN O'Carroll is so much a TV institution his Mrs Brown's Boys sitcom is set to run at Christmas until 2020, at least.

Brendan's stage shows are so successful they generate enough revenue to make a serious dent in the Irish National debt.

But in the build up to Mother's Day, how much did the Dubliner's own mother Maureen O'Carroll play in his success?

Poet Philip Larkin wrote; 'They mess (not actual word used) you up your mum and dad,' suggesting parental nurturing can be far more powerful than natural imprint.

And while Brendan believes his mammy didn't wreck his life, he admits she certainly instilled in her little boy the character traits needed to create the success story he has become.

"My mammy told me I was the 'Special One'," he says. "I was the last to arrive of the eleven kids and unexpected - the doctor told her she had a growth which turned out to me - and because of this I was treated like the Baby Jesus.

"Right from an early age, my mammy told me I was blessed, and could do anything I wanted in life."

Maureen O'Carroll led by example, despite having a family the size of a football team, she became a Labour MP in the Irish Parliament and a women's rights campaigner.

"Yet, the irony is none of her own kids made it past Primary. We all went out to work. I was a waiter from the age of twelve. But what this experience taught me was to think on my feet.

"I learned to please people. I learned how to make people smile and they gave me tips."

However, Brendan's first audience was his Mammy. "Growing up, with the others older and my dad dead, it was often just me and her in the house.

"And I loved to make her laugh. I'd take the false teeth from her mouth at times, I'd make faces, do impressions and voices. And she loved it."

But not always. Maureen O'Carroll could register her disdain. She was often the most demanding of audiences.

"She could make you feel a million dollars one minute, and make you want to slide under the door the next," says Brendan. "But I always wanted to please my mammy. I wanted to make her happy."

He didn't know the term passive-aggressive at the time but Brendan innately he came to understand his mammy could be sweet as the first sip of Guinness one minute - and a demanding drama queen the next.

And because of this loving, but at times mercurial personality, the mammy had her youngest eating out of her hand -hanging on to her every word.

And because she expected so much of him, Brendan supplied. He'd read grown up books so's to impress her.

"I'd study Almanacs," he says grinning "Then I could feed her my knowledge and get the reward of recognition."

Maureen O'Carroll also practised tough love. When Brendan was ten, he was caught stealing from a supermarket in his village, Finglas, in North Dublin.

"I nicked a bicycle repair kit - and I didn't even have a bicycle," he recalls, grinning at the stupidity of it.

"And I was sent to borstal for three months. Now, my mother had influence and she could have kept me out of jail, but her argument was 'You've made your bed, so you'd better feckin' lie in it.'"

Brendan also learned of the value of storytelling . When she wasn't out battling multinationals she and Brendan would go to the movies. "I saw Mary Poppins seventeen times with my Mammy," he recalls, smiling. "And then I'd go home and tell her stories I made up. She loved to hear them."

Ironically, it was the death of Maureen O'Carroll that was to allow Brendan to become a comedian.

He'd opened a bar which went bankrupt after his partner ran off with the money, with Brendan owing £96k, "which may as well have been £96m."

"The bank manager hated me so much you'd think I'd murdered his wife."

Brendan was married at this point with two kids (he now has three, and five grandchildren) and he had to make money fast.

So he turned to comedy, working at first for a tenner a night with comedy partner Gerry Browne.

"But I wouldn't have gone into comedy for a tenner a night if my mother had been alive," he says. "I would have made the pub work. Somehow. I wouldn't have been able to deal with her disappointment in me."

But he didn't. He allowed his imagination to fly. He wrote the Agnes Browne books. He wrote a Mrs Brown radio series.

"Thankfully, by now I was in the career world I wanted to be."

Brendan then decided to write a comedy play featuring Agnes. And it became a massive success for ten years.

And then the audiences died off and Brendan told his cast - all family members and friends - the curtain was coming down for the last time.

Even his mammy couldn't keep this show running. But then fate played a hand. Rab C. Nesbitt writer Ian Pattison saw the show in Glasgow, recommended it to a BBC producer in London - and a national star was born.

"But my mammy was part of this," he says, smiling.

"I made it because I'd kept it all going for so long. Just long enough to get that break.

"It was my mammy who gave me that belief, that anything is possible if you keep trying your feckin' best."

€¢How Now Mrs Brown Cow, the Hydro, March 31 - April 4.