Yes, absolutely, and technically she is not living with you, she's visiting you at your house.
It's not an issue for a married couple, just attach your explanation.
If you need a visitor record extension, that should be done while you are in Canada only but that doesn't give you a right to enter if your visa is expired.
Yes, a good point when it's a PNP but even in that case you can justify it with a job offer, marriage, etc. But, yeah, you have be prepared for that kind of issue.
Not sure you understand or maybe I misunderstood but you mentioned that "They are in Canada with temporary status". So it looks like you do have someone else besides your sister?
Or the other way:
You can sponsor your sister if she is an orphan and she doesn't meet the following:
1 or both of her parents is still alive
no one knows where parents are
parents abandoned her
someone else other than parents is taking care of while 1 or both parents are alive
parents...
If you have any other relative from the list above, you canot sponsor your sister, no matter where they are or what their status.
You need to meet 2 requirements:
1. You don’t have any relative who are PR or citizen;
2. And you don’t have any relative from the list above.
If you meet both...
WP will be issued based on the validity (minus 1 month) of your passport , the one you used in the application. Most likely, a new passport won't help. But you will be apply to apply for extension within Canada.
If you don't have :
spouse
common-law partner
conjugal partner
son or daughter
parent
grandparent
orphaned sibling
orphaned nephew or niece
orphaned grandchild