The mother of six had shared a snippet from a news article about the moments women they knew their marriages were over.
One woman said she had decided to leave her relationship after her husband asked her to be quiet while she was giving birth.
Sharing the screenshot with her followers, Hilaria wrote: “Alex shushed me while I was in labour with Rafa.”
The film director, who was on the phone at the time, told his wife: “Shush! Can you keep it down?”
“The moment he said it he realised he sounded like an ass and he cowered,” Hilaria recalled.
She went on to say that she “kept the marriage” and now only lets him into the labour room after she has had the epidural.
“Went on to have 522 babies after,” she said. “I’ll spare you the details of my reaction for now. But it never happened again.”
The couple, who have been married since 2012, have six children. They have two daughters, eight-year-old Carmen, and baby Lucia, who was born earlier this year.
They also have four sons; Rafael, 6; Leonardo, 5; Romeo, 3; and Eduardo, 1.
In October, Alec was at the centre of an accidental fatal shooting on the set of the film, Rust, which led to the death of cinematographer Halyna Hutchins.
During an interview with ABC earlier this month, Alec said he had been having constant nightmares about guns, and that he hadn’t slept for weeks.
Hilaria has publicly offered her support to Hutchins’ family and Alec. In a post to Instagram, she wrote: “My heart is with Halyna. Her husband. Her son. Their family and loved ones.
“And my Alec. It’s said, ‘there are no words’ because it’s impossible to express the shock and heartache of such a tragic accident. Heartbreak. Loss. Support.”
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