Hello,
I apologize for posting so many questions. It’s just that all of this is so confusing 
It’s seems like one of the documents that need to be submitted is a birth cerificate. My wife (the principal applicant) was born at home so she doesn’t have an official birth certificate. Would her passport be enough as proof of birthdate and if so, how can I explain this in the application?
Thank you again
Hello,
Thank you for sharing your question and situation with us.
According to a CIC representative, in this case, you can write a letter of explanation stating why her birth certificate has not been included in the application.
There are no guarantees however that the application will not processed without the birth certificate.
We suggest that once you arrive and start the application process that you the Citizenship and Immigration Canada (CIC) Call Centre directly.
I hope this information is helpful. Please let us know if you have further questions and if there is any follow up to your question/situation.
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Anna
Settlement.Org Content and Information/Referral Specialist, CIRS
Settlement.Org