It was in the evening, at their home, when the abuse took place.
Judge Farnan said throughout 2017, on multiple occasions, he would take his older daughter into a room, give her an iPad and sexually assault her.
He then repeated that behaviour with the toddler.
The offending escalated at the beginning of 2018 and continued until last October.
The man admitted raping the older child and violating both children during that period.
His offending came to light when he handed himself in to Queenstown police.
A search warrant was subsequently issued and police found a laptop containing an objectionable publication.
He was charged with representative charges of doing an indecent act on a female aged between 3 and 4, and aged between 7 and 8, between January 1, 2017 and December 31, 2017; a representative charge on doing an indecent act on a female aged between 4 and 6, between January 1, 2018 and January 2, 2020; three representative charges of sexually violating a female then aged between 9 and 11, between January 1, 2018 and October 2, 2020; and charges of sexually violating a female aged between 4 and 6 between January 1, 2018 and October 2, 2020, and between June 1, 2020 and August 21 2020; and possession of an objectionable publication, on October 9, 2020.
The man admitted all of the offending and accepted the harm he had caused, acknowledging he had damaged the children "mentally, physically and spiritually", Judge Farnan said.
"It's clear to me ... your victims have been significantly impacted by your behaviour towards them.
"They were entitled to loving and appropriate behaviour from their father.
"You have let them down."
A presentence report detailed abuse the man had suffered as a child. He said he had early exposure to pornography and had abused drugs.
He stated he "did not know how to parent", described himself as "sick and perverted" and said his behaviour was "very wrong".
He did not expect to see his children again.
A psychological report diagnosed him with paedophilia disorder and autism spectrum disorder and found his risk of reoffending was moderate to high.
From a starting point of 16 years' imprisonment on the lead charges of rape and unlawful sexual connection, Judge Farnan applied a global discount of 50 per cent to bring the end sentence on those charges to eight years' imprisonment, with a minimum non-parole period of four years.
She also sentenced him to five years on the remaining charges and made an order for the destruction of his laptop.
He will be registered on the Child Sex Offender register pursuant to the Child Protection (Child Sex Offender Government Agency Registration) Act 2016.
A final order for name suppression was made, "not to protect you in any way, shape or form, but to protect your children".
Where to get help:
• If you've ever experienced sexual assault or abuse and need to talk to someone call the confidential crisis helpline Safe to Talk on: 0800 044 334 or text 4334. (available 24/7)
• Better Blokes which provides peer support throughout Auckland, including a specific Pacific group.
• Male Survivors Aotearoa offers a range of confidential support at centres across New Zealand - find your closest one here.
• Mosaic - Tiaki Tangata: 0800 94 22 94 (available 11am - 8pm)
• If you have been abused, remember it's not your fault.
