Michael McKean Marks 23rd Anniversary with 'Best Friend' Annette O'Toole: 'Thanks for Saying Yes'

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Michael McKean and Annette O'Toole are spreading the cutest couple vibes for their 23rd wedding anniversary.

The pair marked their silver plate anniversary on Sunday with some sweet tributes to each other, as McKean, 74, shared a candid photo of his wife, 69. "23 years ago, I married my best friend and it is working out beautifully. Thanks for saying yes, @creamofwool," he wrote.

"I'll say. 23 years ago today," O'Toole added in quote tweet, sharing a photo from their 1999 wedding day.

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They previously started the day with some cute online banter. "Dear @MJMcKean. Happy Silver Plate Anniversary. Lub, LMM," she wrote, to which McKean responded: "Um…the silver plate store was closed so I owe you. Free for dinner?"

Some of their celebrity friends were feeling the love and helped them celebrate in the replies. "Hooray!!" wrote Patricia Arquette. "Happy anniversary you crazy kids," Seth Green responded. "Awwww. Beautiful. Happy happy anniversary," Meredith Salenger commented.

Salenger's husband Patton Oswalt also marked the occasion. "'Honey! Uhhhhh… did you know that the traditional 23rd wedding anniversary gift is a used VHS tape of CLUE?'" he wrote, referencing McKean's role as Mr. Green in the 1985 comedy.

O'Toole and McKean were friends since the late '70s, often running into each other at parties hosted by Rob Reiner and Ed Begley Jr. Their romance only started after filming their 1998 TV movie Final Justice, which they recalled in a 2018 video for TheaterMania.

The Smallville actress remembered McKean calling her one night after he finished watching ER while she was in bed with her sick kids (she shares two daughters with ex-husband Bill Geisslinger).

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"And I heard it all in his voice. I just heard that he liked me that way," she said, as he added: "I think what you heard in my voice was, 'I'm going all in here.' "

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"And I did something I had only seen in movies," O'Toole recounted. "I put the phone down. I said, 'I really, really want to talk to you but Anna's so sick. Could we talk tomorrow?' He said, 'Yea, I'll call you tomorrow.' I thought, he's never going to call me tomorrow. But I put the phone down and I went into the bathroom and jumped up and down in silent screaming."

The couple ended up having their first date at a UCLA show, where Bob Dylan, Joni Mitchell, and Van Morrison performed, after she helped him shop for a pair of boots, which he still owns today. "I would have married him that day," O'Toole said.