Michael Keaton is mourning costar Teri Garr’s “wonderful” mom

Michael Keaton mourns his own Mr. Mom Kostar Teri Garr, who died on October 29 at the age of 79.

“(T)is the day I feared and knew would come” – Keaton, 73, he wrote on Instagram about Garr, who in 2002 revealed that she had been diagnosed with multiple sclerosis.

“Forget how great she was as an actress and comedian. She was a wonderful woman. Not only are you great to work with, but you’re great to be around. AND go back and watch her comedy. Man, she was great!!”

The pair starred as a couple in the classic 1983 comedy about Jack Butler, a married Michigan dad who struggles with household responsibilities when he is laid off from his job and his wife Caroline (Garr) returns to work. The film, in which Keaton played his first leading role, also starred the latter MartinMull AND Christopher Lloyd.

Talking to PEOPLE during promotions Beetlejuice Beetlejuice in the weeks before Garra’s death, Keaton fondly recalled the time he worked with her.

“First of all, the first thing I’ll say is the fabulous, I mean fabulous legend, Teri Garr, how fantastic she is, how sweet she is and how much fun we had with this movie,” he said.

“Regardless of this movie, if you look at… Just go and watch it Young FrankensteinMan. And she’s still just great,” he added.

Keaton said he knew the script he wrote John Hugheswould be a fantastic comedy.

“I remember reading the script. And I remember laughing out loud three or four times,” he said. “For most people it seems like, ‘Well, it’s not much.’ But ask anyone. Because others that you smile at or smile at, you read and in some way you think about it or imagine it. But if something makes you laugh until you cry, it’s at least encouraging.”

Keaton was right. Due to the chemistry and banter between the two leads, the film received generally positive reviews. It grossed $63 million at the box office (about $200 million in today’s dollars), making it one of the top 10 hits of the year.

Before Mr. MomGarr rose to fame in comedies and starred in hits such as 1974 Young Frankenstein and 1982 Tootsiefor which she received an Oscar nomination for Best Supporting Actress.

Garr died on Tuesday “surrounded by family and friends,” publicist Heidi Schaeffer told PEOPLE.