Life can be full of surprises, but for this couple a surprise came in a very unexpected way.
Kim Guiley and her partner Travis believed they were expecting a baby sister for their three-year-old daughter Hazel - and you can guess what happened next.
Yes, Kim gave birth to her baby, only to realise it was not what they'd spent months preparing for.
"After a couple of minutes, I opened baby's legs and discovered that we had a little boy!" she wrote on the Santa Cruz Family Doula Collective website.
"Shocked is an understatement - I was blown away and totally elated.
"I have always dreamed of having both a daughter and a son but throughout my pregnancy, I had convinced myself we were having another girl."
Luckily, they'd invited photographer Susannah Gill along for the birth, and she captured the moment in a photo that has since gone viral.
Kim and her husband had spent the pregnancy preparing for a girl, even picking out her name.
"We had girls names, we went round and round about girls names," Kim said.
In case you were wondering, they named their baby boy Theo Elliot.
The photo is reminiscent of another now-famous shot of mum getting a surprise on her baby's birth day.
In June, Koko Nakamura gave birth to what she also thought was going to be a girl, after being told it was a female at her scans.
But the baby turned out to be a boy - and photographer Jessica Jackson of Itty Bitty Photography got a hilarious shot of the moment on camera, too.
Photo: Jessica Jackson