When you apply with family there are 2 stages how it works.
Stage 1. When you submit all your family member in one envelope it is considered as family application.
In this case, if any of your family member's document is missing, all of your family's application will be returned.
so when you submit, check 10 times before you send application, because even a minor mistake in a single member's document will returned all of your application.
Stage 2. Let say you pass Stage 1 and CIC send acknowledgement letter.
In this stage, if any issue happens to one family member, rest of the family application will still process.
This is my suggestion and belief to recommend for Family application is that all documents relate to one other and while scrutiny they can match the addresses, job or if you have taken any visit outside of Canada with family then it becomes easy to track them all.
Thanks
canadp
IMPORTANT NOTE: I sent a family application and later on I found out I made a mistake, so I called CIC and agent told me that it will take 3-4 months before your application return, so it would be good, if you send another application rather than waiting for return and then apply again. it will save your time and hence I sent again.
I have mentioned this in other post as well, but for your reference and others I am writing here again.
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In other case, when you send all application individual, it will by default process separately.
