Mandy Moore's latest pregnancy has been "the hardest by far".

The 40-year-old star already has Gus, three, and Ozzie, 21 months, with her husband Taylor Goldsmith, but Mandy has now admitted via social media that her latest pregnancy has been her toughest so far.

Alongside a photo of her growing baby bump, Mandy wrote on her Instagram Story: "Is it September yet? Feeling very grateful to my body AND this pregnancy has been the hardest by far...simply because chasing 2 toddlers is not for the faint of heart. (sic)"

In the photo, Mandy is wearing a skin-tight, black tank top that showed off her growing bump.

Mandy first announced her pregnancy in May.

The actress announced the news via Instagram, sharing a photo of her two sons wearing white T-shirts that read "Big" and "Middle".

The actress - who has been married to Taylor since 2018 - captioned the snap on Instagram: "Sometimes life imitates art. The third in our own Big Three coming soon. Can’t wait for these boys to have a baby sister. [heart emojis] (sic)"

Mandy's social media post was a reference to her 'This Is Us' storyline, as her on-screen character was also a parent to two boys and a girl.

Meanwhile, the brunette beauty previously admitted that she's found motherhood to be a "challenging and rewarding" experience.

The actress also confessed that motherhood has changed her entire outlook on life.

Speaking to PEOPLE back in 2021, Mandy explained: "Being a mom has certainly made me aware of how challenging and rewarding motherhood is."

Despite this, Mandy acknowledged that she's in a much better and more privileged position than many other mothers around the world.

She said: "It truly takes a village. I'm very conscious of how fortunate we are to not have had to struggle to meet Gus' basic human needs.

"There are so many women, moms and their children, who don't have that ability and have to overcome challenges I can't even imagine."