Ilene Asked: What should I do? I’m at a loss?

Okay, so I'm housesitting for a my best friend and her family who live up the street. They will be gone until tuesday. Anyway, they have a dog I'm supposed to watch, and I've been walking it and feeding it and such, but today I looked at their food jar and realized there is only enough left for one serving. I've been feeding the dog the amount they told me too. So I texted my best friend to ask if there was anymore food, and she said they keep it in a container in the garage. So I go in there and I find the container but it's empty except for like three pieces. Well, I'm only fifteen and I can't drive yet, so I can't go to the store and get any. Also, my parents left today to go out of town and pick up my sister from camp. They won't be home until tomorrow at around eight o'clock. So they can't drive me either. All my friends who can drive live far away or are working, and I don't have a dog, so I don't have spare food to give the dog.
I don't know what I should do! I searched the entire kitchen in case there was a bag of dog food but there was nothing. Any ideas?