IRISH TENOR Ronan Tynan says writing a song in tribute to his desperately ill mother was one of the saddest - and most uplifting - things he has ever done.

The star said that he was overwhelmed with golden childhood memories as he wrote Passing Through, one of two songs for his parents on his new solo album, Ronan.

His reminiscences were given an added poignancy by his mother Therese's struggle with Alzheimer's disease, which has left the former schoolteacher unable to recognise her son. 'I wanted people to know this great woman that was behind me,' said Ronan.

Ronan, who wrote the song with composer Margaret Byrne, has also dedicated another track, The Old Man, to his beloved dad, Edmond, who died in 1998, just as his son's singing career was taking off.

Ronan, 44, who was born with a congenital deformity of the legs, said that, while both parents had been an inspiration, it was his mother who gave him the iron will to succeed. 'Her strength was the powerhouse,' he said. 'When I was young and struggling to walk, she would say: "C'mon, Ronan. Don't stop. Move your foot. You can do it."

I never looked on myself as different because I was never treated different. My mother was like every mother, she wanted her baby to stand. 'When people believe in you, you really believe in yourself and my parents - they believed in me.'

The album, Ronan's first since quitting the Irish Tenors, is currently No. 2 in the US world music charts and No. 3 in the classical charts.