Alec and Hilaria Baldwin are having a baby girl.

Hilaria and Alec Baldwin

Hilaria and Alec Baldwin

The happy couple are currently expecting their fifth child together, and in an Instagram video posted by Hilaria on Saturday (12.10.19), it has been revealed they are set to welcome another daughter into their brood.

In the video, the couple's four children - Carmen, six, Rafael, four, Leonardo, three, and Romeo, 16 months - are led into a room by their parents, where they each receive their own baby doll swaddled in a white blanket.

Hilaria, 35, then encourages the tots to open up the blanket to reveal the sex of their unborn sibling.

Carmen - the couple's oldest child, and currently the only girl of the bunch - is then seen excitedly saying "It's a girl!" as she notices the baby is wearing pink.

And the six year old is no doubt thrilled to finally be getting a baby sister after welcoming three younger brothers, as she previously told her parents she didn't want them to have another boy.

Speaking earlier this year, Hilaria said: "When I told Carmen I was pregnant with another boy, she came to me and said, 'Mommy, how about you have another girl then you can have another boy?' And I told her it doesn't work that way."

Asked what she'll do if she has another boy, she added: "I would keep on trying ... I'm serious."

Hilaria and Alec, 61, announced they are expecting a fifth child together last month, five months after the health and wellness expert announced she had tragically suffered a miscarriage.

She wrote on Instagram: "It is still very early ... but we have learned that there is a little person inside of me. The sound of this strong heart makes me so happy - especially because of the loss we experienced in the spring. We want to share this news as we are excited and don't want to hide the pregnancy.

"These first few months are tough with exhaustion and nausea ... and I don't want to have to pretend that I feel ok. My one request is that the media not send paparazzi to follow me or buy independent paparazzi photos, hence encouraging them. I want to remain peaceful during this very early time in my pregnancy and getting chased around by cameras is not in the doctor's orders (sic)"