That makes sense. She probably has outgrown cellos that are normally available for rent.
FWIW, our daughter's 1/2 violin is a H & N and this particular one was much better than anything else we could afford. It 1) has clear and even voice across all strings that projects well, 2) is highly responsive, and 3) can give a wide range of tonal colors. We had to try a whole bunch to find this one.
I'm sure after 4.5 years of lessons, your daughter would like to try out a few instruments and have a say.