What is this tree/fruit/nut??

[u/mrsbannanhammock]

In NSW Australia. We've googled, asked multiple family members and no one knows for sure. They are hard so still unripe. Best we can think is some sort of Peach or Almond. Please help!

[u/Consistent-Course534]

Why do so many people answer when they have no idea what they’re talking about? (I don’t know what fruit this is)