How Can I Legally Claim My Late Father’s Belongings After 13 Years?

I (19F) am seeking advice on how to legally claim my late father’s belongings. He passed away by suicide in 2011 when I was 5, and my sister was 4. In New Zealand, when someone dies without a will, their belongings typically go to the next of kin in this order: spouse/partner, children, parents, siblings.

My mum was unaware of this process, so my grandmother kept most of his belongings, even though some were things my mum had lent him. Over the years, my mum asked for some items back, but my grandmother either claimed they were lost or gave excuses for not returning them.

Fast forward to 2021, we went to spread some of my dad’s ashes at his favorite beach. My aunt (my grandmother’s daughter) started yelling at my mum, blaming her for my dad’s death and saying she didn’t deserve any of the ashes. Since then, our relationship with them has been strained.

In December 2023, I asked my grandmother again about Dad’s belongings. She said she hadn’t had time to go through them and gave excuses. When I asked for a timeframe, she said she couldn’t give one. My aunt also said there wasn’t much of Dad’s stuff left and tried to discourage me from wanting anything.

I’m wondering if there is any legal way to claim my father’s belongings at this point, given that so much time has passed. I’ve heard that legally, we should have received them as his children, but my grandmother and aunt continue to withhold them. Is there a way to take legal action, or are we too late to do anything?

Any advice would be greatly appreciated.