Sienna Miller leaked breast milk all over Mark Wahlberg during their first meeting.
The 35-year-old actress met the Hollywood star at the Golden Globes six months after she had given birth to her four-year-old daughter Marlowe, and Sienna remembers the unusual encounter vividly.
The blonde beauty explained: "I met him just six months after having a baby and I was still breast feeding, but what he doesn't know is that when he very sweetly gave me a big hug I lactated all over him!"
Mark admitted he was completely oblivious to the situation, but he suggested that such bizarre moments aren't uncommon at the annual awards bash.
Appearing on 'The Graham Norton Show', Mark said: "I had no idea! It is the Golden Globes so anything can happen!"
Sienna co-parents her daughter with her ex-boyfriend Tom Sturridge, who she recently hailed as one of her "best friends".
The former couple split in 2015, but have subsequently remained on good terms, living a few streets away from one another in New York City.
She said: "We do bedtime every day. We felt like as much togetherness as possible would be ideal, and fortunately we really love each other and are best friends, and so that works.
"It's not that it's not complicated, because it is."
The 'Lost City of Z' star relishes being a mother, but she admitted that being responsible for a child can feel "crippling", especially when she looks at other people in different situations.
Sienna - who was also previously involved in a high-profile relationship with Jude Law - said: "You're so enriched by it and so fulfilled, but at the same time, I look at these people who just don't have any responsibility, and it feels like the responsibility is crippling."