Hilaria and Alec Baldwin welcomed daughter Lucia via surrogate, a source confirmed to PEOPLE

Girl time.

On Wednesday, Hilaria Baldwin shared a sweet new photo of her newborn daughter Lucia nestled up close with her other daughter, 7½-year-old Carmen Gabriela. "Sisters," she captioned the post on Instagram.

Hilaria also shares sons Romeo Alejandro David, 2½, Leonardo Ángel Charles, 4, Rafael Thomas, 5½, and Eduardo "Edu" Pao Lucas, 5½ months, with husband Alec Baldwin, who is dad to 25-year-old daughter Ireland, as well.

A source confirmed to PEOPLE that the couple welcomed daughter Lucia via surrogate.

The fitness instructor has frequently expressed how Carmen was always asking for a little sister, including back in 2018 when she told PEOPLE that Carmen was "a little bit disappointed" about only getting brothers.

"[Carmen said,] 'How about you have a girl first, then you can have another boy?' I was like, 'It doesn't work that way! I don't get to choose,' " Hilaria said at the time. "She's like, 'No, you don't understand, Mommy. It's going to be a girl.' I was like, 'No, I promise. I promise you it's a boy.' "

Want to get the biggest stories from PEOPLE every weekday? Subscribe to our new podcast, PEOPLE Every Day, to get the essential celebrity, entertainment and human interest news stories Monday through Friday.

Speaking with PEOPLE in November, Hilaria said "during times of COVID, it very much feels like we're done" expanding their family.

"Everybody's asking me this question. I don't know. I've said in the past that I was done when I wasn't done. I think, right now, I'm so tired," she explained at the time. "And I feel, just with COVID — it's just insanity."

Hilaria Baldwin
Credit: Hilaria Baldwin/Instagram

News of her sixth child's arrival also comes a month after the Mom Brain podcast co-host apologized in February for not being "more clear" about her cultural background when she was accused of misrepresenting her heritage in late December. Social media users alleged she had falsely claimed to have Spanish roots and took on a Spanish accent despite being born and raised in the United States.

"I've spent the last month listening, reflecting, and asking myself how I can learn and grow. My parents raised my brother and me with two cultures, American and Spanish, and I feel a true sense of belonging to both," said Hilaria, who previously confirmed that she was born in Boston and her birth name is Hillary. "The way I've spoken about myself and my deep connection to two cultures could have been better explained — I should have been more clear and I'm sorry."