Carrie Underwood ain't afraid of no ghosts. The "Heartbeat" singer celebrated her 33rd birthday on Thursday (March 10) on a ghost tour in Scotland. She shared updates along the way through social media, including her birthday shirt, which read, "I ain't afraid of no ghosts."

Another photo had Underwood sporting a headlamp and special ghost-hunting goggles. Whether she spotted ghosts, Underwood didn't reveal, but the experience would no doubt make for a unique song.

The country singer is currently taking her Storyteller Tour across Europe for the C2C Music Festival. She performs for two sold-out crowds Friday night in Glasgow and Saturday in London before wrapping the tour in Dublin on March 13.

Recently, Underwood celebrated one year of her fitness line, Calia by Carrie. According to a press release announcing the line, Calia by Carrie features “high-quality garments built to support the female body in motion, incorporating functional details and performance-driven fabrics into sophisticatedly feminine designs.” The singer also used her personal style as inspiration.

“It has been such a rewarding experience working with Dick’s Sporting Goods on all aspects of the design process for Calia, from choosing fabrics to making sure the look, feel and fit is right for active women,” she shares. “The inspiration for this line came from my desire to have clothes that seamlessly take me from workouts, to errands, to rehearsals and beyond. As someone who is passionate about health and fitness, I’m excited to offer women a wardrobe that will move with them and encourage them to stay the path of leading an active lifestyle.”

She also recently celebrated her son, Isaiah's, first birthday.

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