New Delhi, Sept. 15 -- To him, she was simply "mama."

Culkin joined O'Hara's "Schitt's Creek" co-stars Annie Murphy and Dan Levy on stage at Monday night's Emmy Awards for an emotional tribute to the revered comic actor, who died Jan. 30 at age 71.

"She wasn't just a wife to Bo (Welch) and mother to Matthew and Luke," Culkin said. "She was my mom. She was our mama, and by extension, she's all of our mama."

Culkin urged viewers to call their mothers and recalled how O'Hara continued to show up for him decades after they starred together in two "Home Alone" movies. O'Hara played Kate McCallister, the frantic mother of Culkin's Kevin, in the 1990 original and its 1992 sequel, two holiday blockbusters that became perennial television favor...