Thomas Rhett Has Hot Tub Party with All 4 Daughters to Celebrate Lillie's First Birthday: Photo

Thomas Rhett is grateful for every moment with his four girls.

On Tuesday, wife Lauren Akins shared a sweet family moment where the country singer, 32, smiles in a hot tub as he celebrates daughter Lillie Carolina's first birthday with all four of his daughters.

"Family hot tub party for Lillie's birthday 🎈🥰💕," Akins captioned the sweet shot, which shows a smiling Thomas Rhett with Lillie on his lap, Lennon Love, 2, on his back and 7-year-old Willa Gray leaning in next to them. Next to her is Ada James, 5, who throws up peace signs in the family photo.

Earlier in the day, Thomas Rhett shared a birthday tribute to Lillie on Instagram, reflecting on the milestone.

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"Lillie bug.. how are you one already? It seems like yesterday. For real," the proud dad wrote. "I love you so much. Every time I look at you you are smiling! Don't ever lose that! Happy birthday to you little baby🙌."

Last month, Thomas Rhett appeared on Audacy's Rob + Holly where he chatted about the experience of working with Katy Perry on their track "Where We Started," sharing that the two "literally talked about our kids the entire time."

"We literally talked about our kids the entire time… how we're raisin' 'em and what we're feeding 'em," he shared. "I think that's what you do as a parent these days, you're just like, 'Oh, let me show you this one picture on my phone of my kid that you've never met!' "

Thomas Rhett told PEOPLE in June 2021 about how he found out his family would be growing yet again.

"We were on a ski lift and my wife kept saying that she was just feeling nauseous and somehow I convinced her it was from her face being burnt," he shared. "I was like, 'Maybe it's just sun poisoning.' Or, 'Maybe it's this.' And she was like, 'I don't know, this feels kind of different.' "

The "Marry Me" artist said he then joked with Akins that maybe she was pregnant again.

"She was like, 'There's no way I'm pregnant.' And I was like, 'Well, there's definitely a way,' " he said with a laugh. "And we went and got a pregnancy test and literally within 15 seconds, there were two pink lines on the pregnancy test."

In May 2021, the artist revealed the news to the world while on stage during his concert in Fort Worth, Texas.