Michael Cawley (37) of Leeside Apartments, Bachelors Quay, Cork pleaded guilty before Cork District Court to assault causing harm to Karen Harrington (38) early last year.
Harrington was last week convicted by a Central Criminal Court jury of beating Santina Cawley (2) to death on July 5 2019 at a Cork apartment complex.
Santina - who was the youngest child of Mr Cawley - died from a traumatic brain injury and a severe spinal injury after suffering a fractured skull and fractures to her arm, leg and ribs while in the care of Karen Harrington.
The murder trial heard there wasn't a part of the little girl's body that wasn't bruised with a total of 53 injuries noted by the pathologist.
Doctors said the injuries suffered by the child were "unrecoverable."
Harrington was the then-girlfriend of Mr Cawley who was separated from his wife, Bridget, with whom he had five children.
The 38 year old had been dating Michael Cawley since December 2018.
She was handed a life sentence after being convicted of Santina's murder by unanimous decision of the eleven member jury following a harrowing four week trial.
Michael Cawley appeared before Judge Joanne Carroll at Cork District Court on a charge of assault causing harm to Karen Harrington last year.
The charge was brought contrary to the Non-Fatal Offences Against the Person Act.
Michael Cawley was charged with assault causing harm to Karen Harrington at Merchant's Quay in Cork city centre on January 26 2021.
Defence solicitor, Frank Buttimer, said his client was pleading guilty to the charge.
However, no details of the incident involved were outlined to Judge Carroll as the State asked for the matter to be adjourned.
Sergeant Gearoid Davis explained that the State wanted to ascertain if a victim impact statement would be required before sentencing was finalised in the matter.
Judge Carroll agreed in the circumstances to adjourn the matter for two weeks.
She remanded Michael Cawley on bail to appear again before Cork District Court on June 8 next.
Details of the incident involved will be outlined on that date.
Karen Harrington of Lakelands Crescent, Mahon, Cork is now entering her second week of a life sentence imposed for the brutal murder of the little girl in July 2019 after she had been drinking for several hours.
Her murder trial also heard that she had been smoking cannabis - and had gone back to her apartment in a very distressed state from a friend's home after being insulted and called "a prostitute" by Mr Cawley around 1.30am on July 5.
Michael Cawley had then left Santina alone in the care of Karen Harrington at 3am - and had walked alone into Cork city centre in search of his cousin.
He only returned to Harrington's apartment at 5am.
Harrington had vehemently denied the murder - but was unable to explain how the toddler suffered such horrific injuries while she was alone with her in her apartment.
Extensive CCTV footage showed the only person who had entered and left the flat with Santina at the time involved was Karen Harrington.
In his victim impact statement, Michael Cawley said he arrived back to Harrington's apartment at 5am on July 5 2019 to discover a nightmare scene.
He said he would forever be haunted by the sight of his daughter fighting for her life and having suffered such disfiguring injuries.
Santina was lying naked and blood-spattered on a dirty duvet with clumps of her hair having been torn out.
Her earring stud had also been torn out.
Karen Harrington was asleep on a nearby couch.
She ran from the scene when Michael Cawley demanded to know what had happened to his child.
Harrington ran barefoot from Boreenmanna Road to a friend's house in Blackrock - arriving with her feet bleeding.
The friend later drove her back to the apartment complex when Michael Cawley, in front of Gardaí, accused her of being "a monster" and of killing his child.