The country star and father-of-three shared a sweet message to Instagram on Tuesday, Dec. 6, in honor of his daughter Audrey’s 21st birthday. “Our baby gurl turns 21 today!!!!” McGraw captioned the post dedicated to Audrey, the youngest of his three daughters with wife Faith Hill. The longtime couple are also parents to daughters Gracie, 25 and Maggie, 24. “We r so proud of the remarkable young woman you have become,” the doting dad continued. “U make this world a better place to be for everyone who loves you.” The post—set to the tune of the country crooner’s very fitting 2006 track “My Little Girl”—featured a video montage of his youngest daughter through the years, starting off with a silly photo from her childhood. “Happy birthday ‘my little girl,’” McGraw aptly added. “We love you so much!” The newly-21 year old—who clearly found some humor in the throwback photos—showed her dad some love in the comments, writing, “Hahahahaha love you dad!! under the sweet post. Audrey’s older sister Gracie also took to Instagram to share a tribute to her baby sis and upload her own share of embarrassing childhood photos. “Happy 21st to my tiny baby sister @audreymcgraw,” she started out her witty caption. “You were the cutest baby in the world and now you’re a hot, intelligent, poignant bitch.” “It is rude to be hotter than your older sister but I love you, so I don’t mind,” the comical caption continued, before things turned more sentimental. “I’m so proud of the work you are doing and the work you are striving for,” Gracie added. “You will do great things my little chicken.” “Love you so so much,” she concluded. Audrey once again responded in the comments, writing to her sister, “HAHAHAH! Gracie I love you so much!!!!” Of course the girls’ mama couldn’t miss out on all the birthday wishes, as Hill also shared her own Instagram post featuring various clips and photos of Audrey. “That’s right, say goodbye to 20 because our baby girl has turned ……21 YEARS OLD today,” the country songstress wrote in her post on Tuesday, while sharing some fond memories of when she first brought her youngest daughter into the world. “Coming into this world almost 8 weeks early with the widest smile on her face and the biggest eyes,” the three-time mom recalled. “I will never forget looking right into those eyes staring back at me saying, ‘what cha’ll worried ‘bout, I’m ready to go….let’s get on with it!!!’” “That spunk and spirit put me right at ease,” she added. “I knew Audrey Caroline McGraw was going to be just fine. She came early for a reason and she was ready to prove it!!!” “Happy Birthday my little songbird We love you so much. Mom,” Hill’s heartfelt message concluded.