My son has these two trees and neither one of them is doing well. The "Tea tree" has wilted, turning brown leaves that look like the fluid has been drained and it has "white bumps" on the leaves. I think I have seen spider mites, at least one, but no webbing on anything. Looks like a fungal issue as well.
The other tree, "Rain Tree" has similar leaves looking drained and starting to drop. Some of the branches look like they are dying, and are brown.
I was reading that the Tea Tree needs humidity and high light for 14-16 hrs a day.
Any help will be very appreciated, as I don't know much about these bonsai. Was thinking about getting some Neem Oil.

Jeanne,
Is it possible to show some pictures of the plants?