Justice Mathew Downs said the case against the war vet was strong and he was confronted with the potential testimony of three victims- all relatives. The offences happened in 2016 and 2017.
The man pleaded guilty on June 5 this year, the same day he accepted a sentence indication from the judge.
His lawyer raised the possibility of additional discount for remorse but Justice Downs wasn't convinced.
"I note you have shaken your head repeatedly as I have spoken to you. I also heard you use the word "lies" when I recounted the facts," the judge said during sentencing.
The man told the pre-sentence writer he committed the offences only after the children were "naughty" in that they kept jumping on him.
Justice Downs said he was troubled by those remarks and the man's conduct in court.
"At best, all this implies you have not yet accepted full responsibility for your actions. At worst, it suggests you continue to pose risk to children.
"You need to reflect on what you have done. Only you are to blame. Unless you come to appreciate this, you may be in prison for a long time."
The man has a possible fluctuating hearing loss and struggle to express himself, perhaps because of a learning difficulty.
His lawyer said medical and other records confirmed a diagnosis of post-traumatic stress disorder in the wake of his war experience, and related depression.
Twelve charges against him were dismissed at sentencing.
