SN11 said:Usually to proove relationship of two siblings father's same name is the only way. If you have their birth certificates coly, you can attach that with a letter of explanation or if you can attach your father's passport copy which has parents name, coz voter ID may not be considered a valid proof. CIC will give more importance to passports which shows parents name is same and birth certificates.
Thanks SN11.
I shared my father and his brother voter card and education certificate.
In case of passport, canadian passport (my uncle) doesnot have father's name.
And my father is no longer in this world so his passport is not available. I explained all this in letter of explanation. Hope CIC takes this into account.