An American woman whose Irish husband killed their three-year-old daughter in Cork has appealed to be allowed to exhume her child's body and take her back to the US.

Rebecca Saunders arrived in west Cork for an eight week study-abroad programme in the summer of 2004.

She met and married a local farmer, 42-year-old Martin McCarthy, and they went on to have a baby girl named Clarissa.

In March 2013, McCarthy drowned Clarissa and took his own life near their home at Audley Cove outside Ballydehob in west Cork.

Ms Saunders had traveled to Bantry that day to seek legal aid in relation to separation and divorce proceedings.

McCarthy and Clarissa were buried together, but speaking on RTÉ's Claire Byrne Live from Houston, Texas, Ms Saunders said she wants now to bring her daughter's remains to the US.

"I remember when Clarissa got back from her post mortem and her coffin was open," she said.

"I just remember always wanting to be by her side and wanting to crawl into that coffin with her.

"I could not believe what was in front of my eyes and what had just happened and how fast everything was going."

At an inquest, coroner Frank O'Connell said he believed Clarissa was restrained by McCarthy under the water, fell unconscious and died.

He said it was his belief that McCarthy decided to end his life and took his daughter with him, and that the evidence - a note left by McCarthy - supported that view.

His last line in the note read: "You will never forget this day."

In a fog of grief, Ms Saunders said she made a decision to have Clarissa buried with her father.

"I agreed to that. It was brought up by somebody else, I did not think of it myself," she said.

"I did not want to think of how I would bury my own daughter, but I thought to myself at the time that I could not handle the thought of having my daughter cremated that time.

"I felt like when the idea came up to bury them together, if she had a choice, if she could make a choice in this decision whether she was going to be by herself or whether she wanted to be with somebody, I just felt like she would not want to be alone.

"I did not realise just how sinister Martin's plan was and how much in advance he planned out what he carried out that night.

"And so I thought to myself; if she had a choice, she would want to be buried with her father ... even though he did what he did, as she would still love him."

Ms Saunders said that ever since Clarissa was buried, she felt as though she had made a "grievous mistake".

She wants to see her daughter's remains exhumed and to brought to the US, where she now lives.

"While I understand the reasons why I decided what I had decided eight years ago, certain circumstances were brought to light that made me realise just how involved Martin's plan was," Ms Saunders said.

"I feel like burying them together was a huge mistake ... I feel like I essentially abandoned her because I'm not there anymore and the grave where she's buried and how she's buried and who she's buried with just gives me a great deal of stress.

"I would sleep better. I would be able to function better if I was able to take her home with me."

Ms Saunders said she knows that exhuming her daughter is not going to bring her back, but said it will be some small amount closure.

"I hate to use that word but that's what it will be when I exhume Clarissa, when I can take her home with me," she said.

"There will be some small amount of closure that I no longer have to think that she's in the arms of that monster."