Jennifer Siebel was born in San Francisco and has a Master's in Business Administration. She worked with Conservation International and traveled to Africa and Latin America to help women build and sustain their own businesses. In 2002, she moved from a California suburb to Hollywood to pursue an acting career and landed small roles in a few key shows like "Mad Men" and "Rent" (via Insider). For a brief time, she dated actor George Clooney before meeting Gavin Newsom. For Newsom, his marriage to Siebel was his second. He was previously married to Fox News commentator Kimberly Guilfoyle for four years, from 2001 to 2005. 

Oddly enough, though Siebel and Newsom had several things in common, they had conflicting political views when they met. Like Guilfoyle, Seibel was also a Republican when she met Newsom. However, she has since become an independent. 

Now the power couple is often recognized for their commitment to social justice and political ideologies that focus on progressive viewpoints, including healthcare for all, cannabis legalization, and housing for the homeless.