My grandmother replied and gave me heaps of information.
I would like to live in Britain one day so I'm more interested in my dad's side. Wow I'm more kiwi than I thought xD (I thought my great grandmother was Irish, but she wasn't after all). She thinks her dad's mum's dad's (who was Australian) parents were most likely Irish too.
My grandfather was definitely Welsh (had the accent and everything). I assume his parents were too but I don't know for sure.
My mum's side, I don't know much about and I don't talk to her or really care. I think her mother was Chinese or maybe it was her mother's parents that were? I assume her father's parents were Singaporean.
But I can still claim Irish ancestry!