Donald Trump Jr. and Kimberly Guilfoyle Are Engaged, Source Says

Astrid Stawiarz/Getty From left: Donald Trump Jr. and Kimberly Guilfoyle

Donald Trump Jr. and Kimberly Guilfoyle are planning to marry, PEOPLE confirms.

A source says the couple, who have been dating since 2018, are engaged. "Kim has been wearing her engagement ring and both are very excited about blending their families," the source says.

A Trump family spokeswoman did not respond to messages; Guilfoyle couldn't be reached.

It's unclear when the couple got engaged. No date has been set for the wedding, according to a source.

Guilfoyle, 52, seemed to hint at the news in the caption of an Instagram post on Saturday. The slideshow of images showed her and Donald Trump's oldest son at Mar-a-Lago, where she looked to be wearing a large diamond on her ring finger.

"Tonight was extra special celebrating @donaldjtrumpjr's birthday," she wrote. "Don, you are strong, smart, courageous, funny and the love of my life. I can't wait to spend the rest of our lives together. Love you."

The Daily Mail was first to report news of the couple's engagement.

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A former Fox News host and prosecutor-turned-Republican aide, Guilfoyle has been dating Don Jr., 44, since around the time his ex-wife, Vanessa, filed for divorce in March 2018.

Guilfoyle was serving as vice chair of pro-Trump political group America First Action. She has said she's known the Trump family for more than a decade and in 2017 said she had been in talks about becoming the first Trump White House press secretary.

Don Jr. has five kids with Vanessa — Donald III, Kai Madison, Spencer Frederick, Tristan Milos and Chloe Sophia — and Guilfoyle shares a son, Ronan, with ex-husband Eric Villency. She was also previously married to now-California Gov. Gavin Newsom.

Don Jr. helped run the Trump Organization while his father was president and was a vocal defender of the administration's many controversies, adopting a similarly provocative, fight-starting style on social media and on cable TV.

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Since former President Trump left office in January, Don Jr. and Guilfoyle have stayed close to his dad's Palm Beach club. They bought their own home in Jupiter, Florida, last year.

The $9.7 million, 11,300-square-foot estate is located in Jupiter's Admiral's Cove neighborhood, about a 20-minute drive from Mar-a-Lago.

"Only a handful of houses in the 188-home community have this much backyard space," Realtor Rob Thomson of Waterfront Properties and Club Communities in Jupiter previously told PEOPLE. "Don Jr. is a family guy and his children live close. The space for the kids is ample."