. >>> plus, in the zone, how caroline marx became one of the top professional surfers in just three short years, and she's only 16. >> even if i didn't get paid, i'll still surf every day. >> how this teen's career has turned into a family enterprise, but first, the "nightline" five. >> bye-bye. >> you good? >> yeah. >> alexa, turn it up. >> here's your reminder. laura says the teething ring is in the freezer. laura's scheduled a playdate for 3:00 p.m. i'm reminding you. y laura loves you, and you're doing a great job. laura loves you, and you're doing a great job. >> number o ♪ ♪ ♪ raindrops on roses and whiskers on kittens ♪ ♪ bright copper kettles and warm woolen mittens ♪ ♪ brown paper packages tied up with strings ♪ ♪ these are a few of my favorite things ♪ ♪ ♪ he could possibly... he likes to collect things. oh! wow, you got all this stuff from ikea? what do you like not let your kids in here? oh, no, they moved in here. here. this is where i hide all the cords and the remotes, and those clack-clack-clack things. oh and we have an entire comic book store and i managed to wedge a can

. >> reporter: it's just after dawn, and 16-year-old caroline marx is getting in her zone. about to compete against some of the most decorated surfers in the world. on land, she stands only 5'5", but in the water, she's a giant. >> caroline marx, a seasoned, crusty veteran at the age of 16. >> i'm grateful for the opportunity, and it's really fun. >> reporter: on some levels, she's just getting started. this is her a couple years ago. these days, she drips confidence and moves with style, a ride and rise that's taken her as high as number three in the world. >> it definitely happened really quick, that's for sure. it definitely went super fast. now i'm on the world tour. >> reporter: caroline is the youngest surfer ever to qualify for the world championships tour, we're talking about the super bowl of surfing. born and raised in florida, she's the third of six children. her brother luke marx is a pro surfer, too. she says watching her big brother ride and compete back in the day planted the seeds for surfing. marx was dominating. >> the rookie sensation out of florida. big