A little help!?

Hey guys,

WOW. its been AGES since i've logged on here.
Anyways, I really need some help.

My baby, Oreo, seems to have a URI.
He is going to the vet today.
I wont be going with him, my sister will as she can drive and I cant(bummer)
And I'll have to take her place at her job in order for her to make the appointment today, because I dont want to have to wait and make the problems worse.

Oreo has had sneezing, wheezing, and discharge from his nose, crusty eyes and nose. And rapid weight loss. Also, he eats and drinks fine, but, whenever I go to feed him hay or veggies, its like he struggles to walk to it, but I can tell that he is trying.
This seems to have happened overnight, all of these symptoms happened yesterday, and it was unexpected, because the day before he seemed happy as ever when I bought him veggies.
The weightloss was also pretty rapid.
He seems to have gotten only slightly better since yesterday.
and now he's eating some hay.

Anyways, what I need some help on is, since Im not going to the vet, I want to give my sister a list of what she should ask and look out for, because she is not so cavvy savvy.
What should I put on that list?

And also, do you think my baby has a chance of living?
Given the symptoms above, I dont have much hope, but I just wish that I was wrong..