Very often prospective immigrants to Canada are under the impression that they can leave their children and spouses (husbands and wives) behind and later sponsor them. It is true however they must remember that omitting family members on the application (not writing down their information) will be considered as misrepresentation. You cannot later, when sponsoring your family into Canada, say that you forgot to mention them in your application at the time you were immigrating to Canada. It would not matter that you did not know immigration laws of Canada. Your family would be refused and no humanitarian ground would be applicable.
I had a case in the past when a mother was trying to sponsor her student daughter into Canada. Her immigration consultant in Ukraine suggested her to not mention her daughter at the time of the mother’s application. Later on, she tried to sponsor her and was refused as our officials did not have power to consider her daughter as a “family member class” because she did not disclose her existence initially on the application. We appealed the negative decision on humanitarian and compassionate consideration to the Immigration Appeal Division and failed. An adjudicator (judge in immigration tribunal) did not have power to allow the application just because the Immigration and Refugee Protection Act was clearly dictating that she was not a “family member”.