I am currently living in the US under a TN working Visa, my mom just got her citizenship through her dad, Can I get the green card through her?

There are two things involved here for you to obtain the benefit from your mother. The first is the length of time and the second the TN status that requires nonimmigrant intent. If your mother sponsored you, it would be under the F-3 category for married sons and daughters of US citizens. For Mexican-born, only those who applied before June 15, 2001, are receiving final interviews. So that is a wait of over 20 years. The second issue is that TN is not a dual intent visa under which a person can intend to immigrate while at the same time receiving the TN visa. Luckily, most consular and CBP officers would take into account the length of time that the F-3 application would take, and would accordingly still allow you to enter the US with TN status even if you have a pending or approved immigrant visa petition under that category. Due to the limitations of the Lawyers.com Forums, Alan Lee & Arthur Lee, Esqs.’ (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.