"Today is Mother's Day
, a day most people spend with their mothers thanking them for everything they do. But, for me, I can't spend this day with my mom because she's in heaven," Kaileen wrote to Swift. "Last January, my mom passed away and a piece of my heart left with her. My mom was my best friend, the one I laughed with, the one I cried with, and the one I loved with my whole heart. For a while, I felt empty."