A southeast Queensland man has denied committing sexual offences against his son and daughter more than a decade ago, saying he "tried to be a proper parent".
The 60-year-old man pleaded not guilty to 12 charges including three of rape at the start of his trial this week in the Brisbane District Court.
The man from the Redlands, southeast of Brisbane, is accused of having a sexual relationship with his daughter for about half a decade from the time she was about three years old.
He is also on trial for nine offences against his son including assault, indecent treatment and rape.
The man said he drank alcohol, mostly vodka, from late in the day while closing his business, but denied it affected his mood or behaviour.
He admitted raising his voice and "sometimes" losing his temper with his children, but only yelled "possibly a couple of times" when disciplining them.
"I tried to be a proper parent," he told the jury on Thursday.
His barrister Simon Lewis said some alleged offences occurred up to 16 years ago and questioned specific details the children remembered about circumstances at the time.
The pass of time made the general allegations "almost impossible to be defended", Mr Lewis told the jury in his closing address.
He said the man clearly lived in an unhappy home, with issues still lingering between him, his ex-wife and their children.
The trial was told earlier the man allegedly committed offences against his daughter in her bedroom mostly while her mother was away.
He is accused of assaulting the girl if she resisted, sometimes kicking her.
The man allegedly also locked her in a garage cupboard, sometimes for "several hours", prosecutor Jennifer O'Brien said.
The nine charges relating to the man's son include digitally raping the boy when he was about seven and threatening to kill him if he told anyone.
It is alleged the man also struck the boy over the head with a liquor bottle at their home, knocking him unconscious.
The trial continues before Judge Julie Dick.
