PHOENIX - They say it's what's on the inside that counts. Angel Sanchez has a big heart, but, medically speaking, what counts for her is failing, starting with her vision.

"I ask God, if he's going to take my daughter, to take me too,” said Christine Cordova, Angel’s mother, who is trying to come to terms with the fact that doctors can’t even tell her how long her daughter will live.

Her condition is so rare, doctors have flown out just to shake her hand.

That’s why Angel has a bucket list at only 17 years old.

Her brother's biggest fear is “that she'll not be able to see and help herself,” said Ruben Rivera. “I just want her to live the best life she can."

Angel has been diagnosed with scimitar syndrome, which affects the one lung she was born with.

She also has a heart defect, and glaucoma is already rendering her legally blind.

It’s a scary thought for a young girl to eventually completely lose her sight when there is still so much to see.

So, her family is working to check off one of Angel’s bucket list items.

Her brother is raising money for a trip with her siblings to see a Caribbean sunset in the Dominican Republic before she goes completely blind.

But it's more than just a Caribbean vacation or seeing a sunset.

"She said, 'I don't know if I'll be able to see my sisters again,’” said her mother. "She wants to make sure she tells them she loves them. Just in case, she says, something happens to her.”

Soon, a seeing-eye dog will join this family, thanks to the Make-a-Wish Foundation.

Angel said she enjoys learning braille. She uses a walking stick in the meantime, and while she does have some vision in her left eye, she uses a magnifier to get by.

Obstacles and all, she's enjoying life and soaking in all the smiles and affection she can.

Other items on her bucket list include getting a new bed and going zip lining.

If you’d like to help her family take their final trip together before she loses her eyesight, you can donate money to their GoFundMe