Hey Kaitlyn, what would you say her primary usage of the photos is? How much quality does she actually "need"? I regards to photo quality I would just snap a few pictures of the things she typically photographs with each device, and compare on the computer. She might have a big preference one way or the other. It's tough for me to imagine there being a massive difference in quality, but a simple five minute test should give a ton of insight.
In my mind the main advantage of a dedicated camera over a phone is the amount of control you have with the former, but looking over the Amazon page it seems like there aren't really any manual modes for the Canon. So I think that ultimately it will come down to what you mentioned - the convenience of carrying around one less device versus the potential easier usage of the Canon.
Funny that you should ask this question now, I just bought my mother an iPhone SE to replace both her crappy Android phone and a Sony point and shoot. It will be interesting to see how happy she is with it.
I do think that these are two pretty good options, and from an image quality standpoint she will probably be happy with either one.
T5i. Standard Canon zoom. Big Canon zoom. Wide Canon zoom. Plasticy Canon prime. Sony a6000 and a bunch of crappy old lenses plus a Samyang 12mm 2.0. Pentax K-5. Manfrotto tripod and head.