We crated our pug and boxer from the first day we had them (9 weeks), dogs do not like soiling near there beds and it helps when your toilet training! Stopped using the crates when about 12 months old and never had any problems at all, mind you winnie (pug) likes to sit on the top of the sofa looking out of the window watching the world go by if we do go out!
Pugs love company, human or canine, thinking about getting another pug now we don’t have our boxer anymore!