Macaulay Culkin is mourning his friend and former costar Catherine O'Hara after her death at 71. Culkin wrote on Instagram, "Mama. I thought we had time. I love you. I'll see you later." O'Hara died Friday at her home in Los Angeles following a brief illness, her manager confirmed to Us Weekly. A Los Angeles Fire Department spokesperson said paramedics were called to her Brentwood home at 4:48 a.m. and took her to the hospital in serious condition.