Hmm. That's very odd. I just tried it out with a test character and I can't reproduce the problem. :(
You're using the 3.5 sheet available through the drop-down, not the tabbed version you'd have to install manually? (*shouldn't make a difference; the code is/should be identical and I can even switch between them without issue but I'm grasping at straws here...)
Which browser is she using? Is she editing it while popped out or not? Is she using the Roll20 App?
Could she maybe have an addon which is interfering?
https://wiki.roll20.net/Solving_Technical_Issues Does it work if you try editing one in for her?
If you want, you could PM me a link and I could hop in and see what I can (though I don't have any special powers or anything... ) (and can't promise *when* I'd be able to hop in.. dinner's almost ready.... :D