@ Awoderu,adding them is a two way things. There is what they call ''FOSS'', VO always check for this to know if they have a recorded history of any applicants. Through this, they will know about your cousin/nephew denial and will tender your application to more scrutiny and would want to establish the evidence if they are truly your dependant or Not.Then, how do you demostrate this, is by given VO the evidence that you are responsible for their welfare in Nigeria, like evidence of their school fee receipts showing your name as depositor/Payee,letter of consent from the original parents, photo collections of you and your nephew since the date you are responsible for their welfare up to the moment of your application. Besides, be ready to face interview if you choose to add them to your application.Awoderu A.A said:If you try to update the Visa Officer would suspect something fishy. He/she would wonder how you could possibly forget to fill your dependents name in the form. Is it still possible to add to the dependants at this stage. I am thinking of adding that nephew of mine that was denied the visa under the adoption of my brother.
Another thing is that you can add them to your application on the addittional family form, and sponsor them while you are in canada through PNP Program in the province you reside.
http://www.cic.gc.ca/english/immigrate/sponsor/index.asp