Keys To My Life review: Eilish O'Carroll on finding love – 'We were ...

Sunday night is something RTÉ does well. It’s the stamping ground of Dermot Bannon’s Room To Improve – less television show than site of ancient worship for the property-obsessed – and of recently-wrapped mega-hit Dancing With the Stars. It’s also the regular berth for Brendan Courtney and Keys To My Life (RTÉ One, Sunday, 7,30pm), an agreeable blend of froth and tears in which celebrities visit old homes that hold particularly vivid memories.

That formula remains intact as Courtney taps on the door of Eilish O’Carroll, older sister of comedian Brendan and a star of beloved chuckle-fest/crime against comedy Mrs Brown’s Boys (delete according to sense of humour). O’Carroll makes for engaging company, while Courtney is an appealing guide – mischievous as needed, empathetic when required.

Eilish has lived quite a life. Her mother, Maureen, was a pioneering Labour TD and one of the first female politicians to hold the position of parliamentary chief whip anywhere in Europe.

She and Courtney visit the old family home in Finglas, Dublin, to which they moved when it was sparkling new suburb. O’Carroll becomes emotional, recalling her father’s death in his 50s and her mother’s grief.

“I used to hear her cry at night time,” she recalls. “She’d be crying in her bed and I’d be crying in my bed, out of sympathy.”

Worse was to follow. O’Carroll relocated to the UK in her 20s. She lived in Reading, just outside London, where she was trapped in a violent marriage. “It was a very abusive relationship,” she says as she and Courtney step into her former home in the UK.

The trauma comes rushing back. She explains that she experiences the hurt not at an intellectual or even an emotional level – but a physical one. “It feels like somebody has just kicked me in the stomach,” she says. “I was a sad woman then. I can’t fix that.”

The story is full of twists. O’Carroll had moved on and remarried when she fell in love with a woman. “We were both straight women living a straight life. Lesbians – what do they look like? My biggest problem was my Catholic guilt.”

Confused, she returned to Ireland and rented a house in west Cork. She met her partner Marian O’Sullivan in Cork City, moving back to Dublin when her brother’s slapstick alter ego Agnes Brown became popular in the UK – first on stage, then television.

She started working behind the scenes on Mrs Brown – but was then promoted to the part of Agnes’s best friend, Winnie. Fame – and wealth – followed. It is the upbeat ending she deserves and an optimistic conclusion to a moving episode.

“My fortunes changed. There was so much I was able to do,” O’Carroll says of Mrs Brown’s Boys and its transformative impact on her life. But then she shakes her head, a note of sadness in her voice. “You never forget what you didn’t have.”