Through the investment option (not marriage), you can apply for citizenship and include your two minor children to your application, provided that the consent of their father/mother (whichever is applicable in this scenario) is obtained.
How can I get Turkish citizenship for my minor children?
I have 2 minor children from a previous marriage and two from my present marriage of a Turkish citizen, (these 2 kids are Turkish citizens by birth). I want to apply for Turkish citizenship for me and my other 2 kids. Will they automatically become Turkish citizens with me or do I need to apply for them separately? What is the best way to get them citizenship? We are married and live in the U.S.
Children from an investor's previous marriage can acquire Turkish citizenship, provided their mother gives her consent. It is not necessary to make separate applications for these children and their Turkish citizenship applications can be filed along with that of the investor.
If a parent wishes to apply for Turkish citizenship through investment, the application can be expanded to include minor children as well. However, in your case, if you will apply for Turkish citizenship based on your marriage to a Turkish citizen, your children from another marriage will not benefit and will not be able to obtain Turkish citizenship through you. You could still use the investment option rather than marriage and include your minor children without Turkish citizenship in your application; however, the father of those children would still need to approve.