Two years ago, Guardian contributor Shadi Khan Saif fled Afghanistan for Australia, hoping his wife and young children would soon follow him. But he is still waiting to be reunited with them. On the second anniversary of the fall of Kabul he speaks to Jane Lee about the heartbreak of being separated from his family and why he wrote a public letter to his son. And Guardian Australia reporter Ben Doherty tells us why so many Afghans seeking safety in Australia are still separated from their family