Sponsoring the spouse and new born baby (Conceived through Donor Sperm)

Hi, I am a permanent resident here in Ontario and i got my immigration under skilled professional category. My wife also got immigrated along with me in 2009 as my wife. Due to personal issues we got separated and i went back to the Gulf country from where i applied the immigration visa and started my job there but my spouse stayed here in Canada. There one lady came into my life and we start living together as common law partners with great understanding and love.

Since I was already married and my wife already been in Canada, I planned to come to Canada to initiate the divorce with her. I have infertility issues with me and because of it my common law partner was unable to conceive so we both decided to go for Donor Sperm. As it was not legal in that gulf country, she travelled abroad and went through the process and with the grace of God she got pregnant. After some months of her pregnancy I left the country and came to Canada and filed the divorce application in a court through lawyer. Recently I got the Divorce Judgement from court and soon I will apply for the Divorce Certificate. In meanwhile, my common law partner delivers the baby safely and she has put my name as Father in the Birth Certificate. Since soon I will be going to her country (she is a european citizen) to get married with her. After getting married to her I will sponsor her as my wife and also our child.

My Question is that since our baby is not my own biological offspring and borned before getting married to my common law partner, so once I will sponsor my spouse and child to join me in Canada as residents, will Canadian Immigration will ask for DNA verification as the baby born before we get married. Because if they do so then i cannot prove it. Or do I have to delare this in the papers while applying for their sponsorship?

Thanks