A 41-year-old man has been sentenced to seven years in prison - with the final three suspended - after he pleaded guilty to dangerous driving, which caused the deaths of two sisters in Co Galway.

Two-year-old Kate Gilmore and her 12-week-old sister Grace died following a collision on the outskirts of Tuam in October 2012.

John O'Connor, with an address at Waterslade Downs, Tuam, Co Galway, was sentenced at Galway Circuit Criminal Court today.

During the hearing, State prosecutor Patrick McGrath SC outlined the sequence of events leading to the tragedy on Sunday 21 October 2012. 

He told the court that Kate and Grace were taken for a walk by their father John that afternoon.

The children were both sleeping in a buggy and were on their way home, facing traffic heading northwards on the N17.

At around 12.35pm, a red Toyota Avensis driven by O'Connor veered into the hard shoulder and struck the buggy.

The sisters suffered "catastrophic injuries" and were taken to Galway University Hospital, where they were pronounced dead soon after admission.

Mr Gilmore also sustained injuries in the collision.

The court heard that O'Connor had a history of epilepsy and had been treated for seizures since childhood.

He had been seizure free for a number of years following surgery, until a recurrence of attacks in February 2012. 

Superintendent Gearoid Begley told Judge Rory McCabe that a doctor administered medication to O'Connor at the scene of the fatal crash, as he appeared to be having an epileptic fit.

In garda interviews after the crash, O'Connor told detectives that he had been medically fit to drive until June 2012.

He had no recollection of the incident and no recall of an earlier collision he was involved in minutes before the fatal crash.

John Jordan SC for O'Connor said his client had expressed sincere and profound remorse for his actions.

He said O'Connor had reduced intellectual function and was of good character. He had entered a guilty plea as soon as possible.

O'Connor was called to give evidence by Mr Jordan. He said he wanted to apologise to the Gilmore family.

He said he thought the family would be "a million below zero" after what had happened and he was sorry for what had happened to their daughters.

In victim impact statements read to the court, the girls' parents spoke of their loss and effect it had on them.

Mr Gilmore said there were no words to adequately describe the void in his life since October 2012.

Michelle Gilmore said she was haunted by the loss of her daughters.

She said her life had been shattered and that she experienced an emptiness that would remain with her forever.

Judge Rory McCabe described the victim impact statements as "heartbreaking and harrowing".

He offered his personal sympathies to the parents and said it was a credit to them that their statements did not contain a word of bitterness towards the accused.

Judge McCabe said taking into account the mitigating and aggravating factors in the case, he was imposing a sentence of seven years imprisonment, with the final three years suspended.

He banned Mr O'Connor from driving for 20 years and said he can only reapply for a licence after that time following expressed medical approval. 

The Gilmore family have appealed for privacy.