Krystal Keith introduced her new daughter to the world with a heartfelt message and a few sweet photos.

Keith — the daughter of country star Toby Keith — turned to Instagram to share that she and husband Andrew Sandubrae welcomed Kirby Kaye on Tuesday (Jan. 29). A photo shows a close up shot of the sleeping baby wrapped in a beautiful floral blanket as Keith plants a gentle kiss on her cheek.

"When you thought you had loved as big as you ever could. And then in a single moment, the size of that love doubles," the second-time mom lovingly writes alongside the photo, calling Kirby a "sweet girl."

The couple are already parents to 3-year-old daughter Hensley Jack, born in October 2015. "We are happy and healthy. Hensley Jack is the best big sister and Drew is way out numbered with a house full of girls and wouldn’t change a thing."

Keith shared other adorable updates from the big day, including one of Hensley playing doctor, dressed in bright pink scrubs engraved with the phrase "Big Sister," smiling with a stethoscope around her neck.

"Dr. Big Sister reported for duty on delivery day and took all the stats on her “telescope," Keith narrates. She also shared a precious follow-up photo of Hensley adoringly curled up beside her new sister, a moment Keith describes as one where Hensley "MELTED into a puddle of snuggles."

Keith announced she was expecting again in July of 2018, with a video of Hensley holding a baby doll and revealing the exciting news. Keith followed in her father's musical footsteps to become a country singer, releasing her latest EP Boulder in 2018.

"I think it speaks volumes that the way I kind of remember childhood is I don't really remember him being gone," she describes of her dad. "When he was home, he was so present that I don't remember the spans of him being gone."

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