Macaulay Culkin has gone from "Home Alone" to the iconic Hollywood Walk of Fame ... reuniting with his former costar Catherine O'Hara 33 years after the festive classic.

Catherine gushed over his "perfect performance" during a heartfelt speech as he scooped a coveted Star during the ceremony in Hollywood Friday.

The event was also a big personal moment for Macaulay as he was supported by fiancée Brenda Song -- and their sons, 2-year-old Dakota and their 11-month-old baby boy Carson ... who made their public debut.

Macaulay later thanked Brenda in his speech ... gushing she was "absolutely everything" and "the best person I've ever known" -- adding, "And, after the birth of our two boys, you've become one of my three favorite people."

Macaulay also delighted onlookers with the movie's iconic quote: "Ya Filthy Animal!"

Unless you've been hiding under a rock ... Macaulay is best known for the role of Kevin McCallister in the OG "Home Alone", which he took on at age 10 ... later reprising his role in the 1992 sequel.

He's worked steadily in the biz since ... and his last acting credit was in 2021 in the 10th season of Ryan Murphy's American Horror Story.