Wickefisto
Tell your friend to take it back to the store she got it from and ask for a refund if they cannot help. Frogs in captivity are not as strong as frogs from the wild; if you want a healthy frog that will live a long time try to buy from a reptile/exotic creatures expert.
I had frogs in high school, they never lived more than a year; that is considered typical for pet store frogs.
a frog who recieves proper care since hatching and who was bred in captivity by a good breeder will be much healthier than anything caught in the wild.
the main issue is decent breeding and care. so often people dont give these animals proper care so they dont live too long
im not saying its your fault your frogs died, i dont know how you were caring for them, where they came from, or anything.