Get out the tissues! Bindi Irwin wrote a beautiful a note to her late Crocodile Hunter father Steve Irwin, following her engagement to her boyfriend Chandler Powell on her 21st birthday. She wrote in part: "Dad, You would be so incredibly proud of [her brother] Robert. He has been such an amazing support during this beautiful new life chapter. I know you'd be beaming with pride when the time comes that he walks me down the aisle." They have not yet shared a wedding date.