For this, it asks for PR cards and proof of they actually living in Canada. I have 2 siblings, 1 that has an expired PR card, but lives and works here, and another with a valid PR card, but lease is not in their name, but have a driver's license with the same address as the lease.
What should I do? Should I just add both siblings documentation? (the more paper/proof the better?)
Add details for the one who has valid PR card. For address proof, you can add any other document - such as bank statement, utilities (electric) bill, phone statement, etc.
