My dad, the Keyblade Master

This is a story of Sora's son, Jack, as he discovers more and more about his dad and "Unkie Riku". Kairi is the mother, but for this story, she died giving birth to their son and Riku took up the unspoken, yet welcomed role of "Uncle". Sora hasn't been on other worlds for years to try and keep his kid safe, but when Heartless and Nobodies start to make a comeback...