The Boys Don't Cry actress and her boyfriend, art gallery director Sinisa Mackovic, were spotted carrying the tot home from a New York hospital on Monday.
And on Wednesday, Chloe officially introduced fans to little Vanja by sharing a family photo on Instagram.
"Welcome to the world Vanja Sevigny Mackovic," she captioned the image, in which she is pictured cuddling her son with Sinisa by her side. "Born May 2nd New York City (sic).”
Chloe went on to share her gratitude for hospital employees for helping to make her feel as comfortable as possible, despite giving birth in the midst of the coronavirus pandemic.
"Thank you to all the staff at Mt. Sinai East for your bravery, perseverance and kindness, especially the nurses for being so gentle and patient," the 45-year-old wrote. "Blessings to all the other families giving birth during this time. #ilovemyboys".
Chloe will celebrate her first Mother's Day on Sunday.