Thomas Rhett gushed that he's "inspired every single day" by his daughter Willa in a touching tribute for her fifth birthday.

Thomas Rhett and daughter Willa (c) Instagram

Thomas Rhett and daughter Willa (c) Instagram

The 30-year-old country star - who adopted Willa from Uganda in 2017 with his wife Lauren Akins, with whom he also has daughters Ada James, three, and Lennon Love, 8 months - took to Instagram to wish his little girl a happy birthday, and hailed her "kindness, selflessness and hilariousness" as he revealed she is five going on 15.

Alongside a series of throwback snaps of Willa, he wrote: “Ok I’m really sorry for all the posts today but we went straight from Halloween to Willa Grays’s 5th birthday.

“WG you continue to amaze me with your heart, your kindness, your selflessness, and your hilariousness. You make me such a better human being, and I’m inspired by you every single day. You may be 5 but you already act like your 15.

“You are the MOST amazing big sister that AJ and Lennon could ask for.

“I can’t wait to watch you grow and be there with you every step of the way. To my beautiful baby girl, happy birthday sweet pea!”

Meanwhile, the 'Life Changes' hitmaker previously admitted he doesn't see Willa as adopted anymore.

He said: "The word 'adopted' doesn't even make sense in my head anymore really. I know that it happened and I remember it very vividly, but it kind of feels like she has just always been here. Even though Willa Gray comes from [a] whole different part of the world, she's ours and it feels like she never wasn't."