Rochester, N.Y. - They are cousins and best friends who have always done everything together, from dancing to hanging out.
Katie Foster and Mareesa Boyatzies are now battling cancer together. They were diagnosed with different types of cancer, just a day apart.
They have kept each other company through grueling chemotherapy treatments.
But even so Katie says not being able to go to school or other events can be isolating and lonely.
Camp Good Days and Special Times invited the cousins on a trip to Florida along with other teens and children battling cancer.
The group packed their bags and flew to Florida Wednesday morning.
Goodbyes were hard, since their parents aren't going on the trip.
Leanne Boyatzies told us: "We've been together so much since she was sick, it's scary having her go, but at the same time, she's been through so much, it's a great feeling."
Lisa and Jeff Foster also were worried sending Katie off alone, but told us:
"It's unbelievable and it's a great for her to be herself again. It's nice."
Their parents hope the teens will check-in with them while they're away, but they also know, they are in good hands with counselors from Camp Good Days and Special Times.
The group will go to Disney, Universal Studios, a Tampa Bay Rays game, Busch Gardens and on a dolphin watch.
There will also be time to relax in the sun. The teens told us they are looking forward to warm weather and being with their friends.
No one deserves this special trip more than Katie and Mareesa.