My MIL finally took the dog to the vet yesterday.
I guess he didn't make too big of a deal about the aspirin she ate since it had been more than 48 hours since she had ingested them.
However, she has some sort of infection in her ears which is why they are swollen and fevered. She is now on some antibiotics and has some ointment for inside the ears.
DH was over there yesterday and he said that she was looking a little better than she did on Wednesday. He, and I, are still furious with the in-laws though. It was totally out of line to not seek medical attention for her right away. Like some other posters have mentioned, if it would have been a kid, they would have taken it to the E.R. right away. Grrr.... I still don't know how my in-laws managed to raise their children to adulthood.