both of my dogs have been rescues. My first akita, Bubba, i adopted from a friend who was moving out of the country.
When i got him, he was 4 years old. For his first four years, he lived with a tawny pug, just like yours.
for the entire 12 years i had him, every time he saw a pug, he would go nuts trying to get to it to play. I think he missed his "big" sister.