Sorry to hear about your loss.

Gail is spot on with her questions but you might want to fill out the trouble in the enclosure section here to give us a better picture what's going on.
If there's any way possible you can move the enclosure to a cooler area like a basement that would be preferable.
Hopefully we can work out a solution and save your other baby best wishes.

1. Size of enclosure
2. # of inhabitants - specifically other frogs and size differences
3. Humidity
4. Temperature
5. Water - type - for both misting and soaking dish
6. Materials used for substrate
7. Enclosure set up i.e. plants (live or artificial), wood, bark and other materials.
- How were things prepared prior to being put into the viv.
8. Main food source
9. Vitamins and calcium? (how often)
10. Lighting
11. What is being used to maintain the temperature of the enclosure
12. When is the last time he/she ate
13. Have you found poop lately
14. A pic would be helpful including frog and enclosure (any including cell phone pic is fine)
15. How old is the frog
16. How long have you owned him/her
17. Is the frog wild caught or captive bred
18. Frog food- how often and if it is diverse, what other feeders are used as treats
19. How often the frog is handled
20. Is the enclosure kept in a high or low traffic area
21. Describe enclosure maintenance (water changes, cleaning, etc)