Kirke also shared a significant post about being 40 days post-partum. She shared the news with a painting of a red uterus to Instagram.
"His heart shapes home, #40dayspostpartum," she captioned the photo.
In many customs and religions, the first 40 days after giving birth is when the mother is to rest and bond with her baby.
It marks the six-week mark, where the mother has generally stopped bleeding, breastfeeding is likely to have been established and if she has been well-rested and complication-free, she will often have regained her energy.
The child is the first for the singer and Gossip Girl star, however, Kirke has a 10-year-old son with ex-partner Morgan O'Kane.
In February, Kirke announced her pregnancy news which included a photo of her baby bump, along with a post about her previous miscarriages.
"On the road again... pregnancy after loss is a whole other thing. After two miscarriages in a row we were ready to call it. I stopped trusting my body and started to accept the fact that I was done. As a birth attendant, I've seen and heard it all. It takes everything I've got to detach lovingly from the losses I've been present for and be in my own experience,' she confessed.
"When I was pregnant at 25, I knew nothing. I had no community. I dove in blissfully unaware about birth and its mysteries. Now, with 10 years worth of experience to pull from, I treasure my birth community and the knowledge I have.
"You're already teaching us how to stay in the day in a way we've never had to, little one. Thank you."
Badgley and Kirke started dating in 2014, and were married in a New York courthouse in February 2017. Kirke is the sister of actors Jemima Kirke (Girls) and Lola Kirke (Mistress America, Gone Girl).
In December, the You actor couldn't stop praising his wife on her 36th birthday. He called her a "truly radiant soul" who could "spark alight almost everyone you meet."
"You make others happy by you. For me, it is a joy to witness you when you are happy," he wrote in the Instagram post.
"For you, I always hope to be a source of joy. I'm really glad we're married."