Guilfoyle's mother, Mercedes, taught special education, and died of leukemia when Guilfoyle was eleven.
"My mother was just everything to me, I loved her so much, I always wanted to be around her. I loved how I saw people react to her. She was a warm woman who worked in education with people with emotional challenges. I got my sense of giving back and how when you have many blessings, pay it forward", Guilfoyle said in a 2015 interview.
Her father, Anthony "Tony" Guilfoyle, was born in Ennis, County Clare, Ireland, and immigrated to the United States in 1957 at the age of 20. In 1958, while still an Irish citizen, he was drafted and served for four years in the U.S. Army. After being discharged from the army, Tony Guilfoyle took up work in the construction trades. He later became a real estate investor and, until his death in 2008, a close advisor to Mayor Newsom.
Guilfoyle then spent four years in Los Angeles as a Deputy District Attorney, working on adult and juvenile cases, including narcotics, domestic violence, kidnapping, robbery, arson, sexual assault, and homicide cases. She received several awards at the Los Angeles District Attorney's Office, including Prosecutor of the Month.
In 2000, Guilfoyle was re-hired by Hallinan in the San Francisco District Attorney's Office, where she served as an Assistant District Attorney from 2000 to 2004. While Assistant D.A., she got a conviction while co-prosecuting with James Hammer in the 2002 case People v. Noel and Knoller, a second-degree murder trial involving a dog mauling that received international attention. In 2008, she was a member of La Raza Lawyers Association.
It was announced on June 29, 2017, that Guilfoyle signed a long-term contract extension with Fox. However, in July 2018, Guilfoyle was reported to have left Fox News to work for a pro-Donald Trump Super PAC. The Huffington Post reported that at the time of her departure, the network had been in the midst of a year-long sexual harassment investigation into Guilfoyle.
Making the Case: How to Be Your Own Best Advocate
In 2015, Guilfoyle released a semi-autobiographical and advice book titled "Making the Case: How to Be Your Own Best Advocate" on her experiences growing up, working as a prosecutor, and encouraging people to always advocate for themselves.
Trump administration and Trump 2020 campaign
Guilfoyle speaking at a campaign rally in Sun City, Arizona in November 2018
In December 2016, it was reported that Guilfoyle was being considered to serve as press secretary for President Donald Trump. Sean Spicer was considered the front-runner for the position and was ultimately selected. On the May 12, 2017, edition of The Five, co-host Bob Beckel hinted that Guilfoyle turned the job down. However, in an interview with Bay Area News Group on May 15, 2017, Guilfoyle confirmed she was in contact with the White House about the position following Spicer's resignation. "I'm a patriot, and it would be an honor to serve the country", Guilfoyle said. "I think it'd be a fascinating job, it's a challenging job, and you need someone really determined and focused, a great communicator in there with deep knowledge to be able to handle that position." However, on May 19, Guilfoyle said she was under contract with Fox, indicating she turned down the White House. One month later she extended her contract with Fox.
In 2018, The Washington Post described Guilfoyle as a "conservative cheerleader for President Trump."
The Trump campaign is paying Guilfoyle $180,000 a year through the campaign manager's private company, Parscale Strategy. Guilfoyle has been a surrogate on the stump and taken on broad advisory roles. In the Trump 2020 campaign, Guilfoyle managed a fund-raising division. This division paid socialite Somers Farkas to raise money. The fundraising division managed by Guilfoyle was in internal turmoil amid departures of experienced staff and accusations of irresponsible spending.
Guilfoyle gave a speech that was widely described by some observers as unnecessarily loud or unhinged at the 2020 Republican National Convention, while others in media described it as passionate.[dubious – discuss] She was criticized for describing herself as a first-generation American when her mother was from Puerto Rico, and hence, an American citizen.
On May 27, 2006, in Barbados, Guilfoyle married furniture heir Eric Villency. Guilfoyle gave birth to their son, Ronan Anthony, on October 4, 2006. In June 2009, Guilfoyle and Villency announced that they were separating; their divorce was finalized later that year.
In June 2018, Vanessa Trump confirmed that Guilfoyle was dating Donald Trump Jr. Trump Jr. and his then-wife had been separated for nine months when he and Guilfoyle began dating.