His brother, fellow actor Pua Magasiva, died by suspected suicide in May this year. A few weeks ago it was revealed Pua was convicted of assaulting his widow Lizz just two weeks before his death.
Robbie broke his silence over the court case on Christmas Eve, sharing a photo of his brother with the text: "Sometimes the hardest thing to do is to do nothing. Rest now Pua."
Lizz explained to the Herald in an exclusive interview that she suffered regular physical and emotional abuse during the two-and-a-half-year relationship.
Robbie Magasiva ended the video saying New Year's resolutions "don't exist", and wished his Instagram followers a happy 2020.
"You watch tomorrow, I'm going to be really positive," he says.
Domestic violence: Do you need help?
If you're in danger now:
• Phone for police on 111 or ask neighbours of friends to ring for you.
• Run outside to where there are other people.
• Scream for help so that your neighbours can hear you.
• Take the children with you.
• Don't stop to get anything else.
• If you are being abused, remember it's not your fault. Violence is never okay.
Where to go for help or more information:
• Shine, free national helpline 9am-11pm every day - 0508 744 633; www.2shine.org.nz
• Women's Refuge: Free national crisis line operates 24/7 - 0800 refuge or 0800 733 843; www.womensrefuge.org.nz
• Shakti: Providing specialist cultural services for African, Asian and middle eastern women and their children. Crisis line 24/7 0800 742 584
• It's Not Ok: Information line 0800 456 450; www.areyouok.org.nz
Where to get mental health help
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• The Word
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention
If it is an emergency and you feel like you or someone else is at risk, call 111.