Davis announced over the weekend that she has become a first-time mum by adopting a girl who she has named Gemma Rose Davis.
Parker expressed joy at the happy news and referenced the fact that Davis's Sex and the City character Charlotte York Goldenblatt also adopted a daughter.
The actress hasn't met Gemma Rose yet, but is hoping to congratulate Davis in person soon.
Parker told Access Hollywood: "She lives in Los Angeles and I live here [in New York], so I've not met her [baby] yet, but I'm so happy for her and I just could not be happier for Kristin.
"It's a wonderful situation. I know she's wanted to have a family for a long time and she deserves that unique kind of happiness that children bring and I'm so happy for her."
Parker also praised Davis's decision to name the young girl Gemma Rose.
"It's a beautiful old-fashioned name, and Kristin is a really old-fashioned girl. She's a southern-raised kind of [girl]," Parker said. "She has a real traditional streak, so I think it's a beautiful name."
A source close to Davis claimed that the actress has wanted to have children for many years.
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