23 and You and Me by Michelle McCraw

Two strangers on the road to Las Vegas. What could go wrong?

Some might call Gabe grumpy. He prefers safety-conscious. As CEO of the happiest place in Ohio, Beach Island Amusement Park, it’s a responsibility he takes seriously, especially since his parents were killed on one of the coasters there years ago.
Sunny has a different legacy: she’s Hollywood royalty. Too bad she quit her last acting gig in an award-worthy blowup. But even after being fired from her humiliating job as a DNA testing company customer service rep, she refuses to let real-life drama crush her spirit. She takes one thing with her: contact information for a stranger’s siblings – siblings Gabe didn’t know he had. She’ll give him a second chance at a happy family if she has to drive him to Las Vegas herself.
Which is exactly what she does. On the road, snowstorms, a swoonworthy karaoke duet, and motels with only one bed help these two opposites see they’re not so different. But love? That’s a jackpot too unlikely even for Vegas. Or is it?