Dax Shepard thought Kristen Bell had 'fake boobs' for months after they started dating.

Dax Shepard has admitted he spent the first few months of his relationship with Kristen Bell feeling very confused. But his confusion didn’t stem from all of the usual relationship things, like not knowing where they were headed, or trying to decide if he really liked her – he was confused about her boobs. Yes, her boobs.

It all started when Kristen made a joke about her boobs being fake at the very beginning of their relationship. According to the couple – who have now been married for five years – it was the first time they’d ever decided to hang out “intentionally,” and after a group dinner with mutual friends, they went back to Kristen’s place, where they all ended up in her hot tub.

Eventually, they found themselves alone, and that’s when things got weird and kind of awkward.

“Like most guys, unintentionally and perhaps subconsciously, your eyes darted down to my sternum area and perhaps the left and right side of my sternum, which I refer to as my breasts,” Kristen recounted on Dax’s podcast, Armchair Expert last month.

“To diffuse the situation, I said, ‘What are you looking at? My fake tits?'”

Dax, 43, said he had no recollection of looking at Kristen's boobs, but could remember "staring at your ass a ton that night." At least he's honest, right?

He did remember Kristen mentioning her fake boobs though, and just assumed she was being serious, because, hey, this is LA.

A few months into their relationship, Dax said he was trying to be a "good boyfriend" by watching Kristen's show, Veronica Mars, when the 37-year-old brought up her "fake boobs" once again.

"Between seasons one and two, you came into the room and said, 'Oh, look at this. This is when I got my boobs,'" he recalled.

But Kristen insisted she was only making a joke about how "late I went through puberty."

"My body was still rearranging itself in my 20's. I lost my chubby cheeks and I got hips and I got boobs when I was 24 years old," she explained.

"I was like, I actually have a boob that someone will recognise as more than a raisin."

Dax still didn't seem to get it though.

"From my point of view, you'd said, 'Look at my fake tits,' and then, 'Oh, this is when I got my boobs,'" he clarified.

To make things even more confusing for the poor guy, Kristen had a habit of pointing out girls with fake boobs and then making jokes about them.

"The first few times it happened, I didn't say anything. I just thought, 'Oh, that's weird. She has fake boobs but she's making fun of people with fake boobs,'" he confessed.

Things eventually came to a head while they were in Hawaii on a holiday, with Dax deciding to confront Kristen on her fake boob prejudices after deciding he was in a no-win situation.

"Finally, I broke and said, 'What do you want me to do right now? I feel like this is a test. Should I join in and comment on these boobs?'" he revealed.

Kristen found the whole situation hilarious, and was surprised Dax could ever think she had fake boobs given she was only an A-cup.

"You thought I purchased these and this is what I got? I was ripped off," she told him.

LISTEN: Are your nipples in fashun? Post continues below.

But Dax admitted the perkiness of her boobs had him confused. When Kristen asked him about the fact she didn't have any scars, Dax just said he thought she'd had a "high-end boob job".

He said he was thrilled when he found out her boobs were real, because he'd been completely "uninterested" in them two seconds earlier, when he thought they were fake.

"When I found out those things were real and they were that perky, I was very excited. There was a huge shift," he admitted.

Shout out to all dads! Here at Mamamia, we are always looking for ways to make Mamamia even better. Dads, we need you to help us do that by filling out this quick 15-minutes survey for us. Click the button below for your say.