All About Joshua Kushner, Karlie Kloss' New Fiancé, and Brother-in-Law to Ivanka Trump

Supermodel Karlie Kloss on Tuesday announced her engagement to her boyfriend of six years, Joshua Kushner, a venture capitalist and entrepreneur who is the younger brother of President Donald Trump‘s son-in-law and senior advisor, Jared Kushner.

The engagement saw the political and fashion worlds colliding, as emphasized by first daughter Ivanka Trump‘s warm well wishes to her new “sister” Kloss on Tuesday.

A source close to Kloss, 25, and Joshua, 33, confirmed the engagement to PEOPLE on Tuesday, saying, “He proposed a few weeks ago during a romantic weekend together in upstate New York.”

The source adds, “They’re both overjoyed and happily celebrating. Their hearts are full and they’re excited to build their future together.”

So who is Joshua Kushner? Here’s everything you need to know about Kloss’ new fiancé.

1. The couple have been dating since 2012 but are typically very private about their relationship.

Despite their high public profiles, Kloss and Joshua have managed to keep their relationship relatively out of the spotlight — attending just a handful of red carpets together (including this year’s Met Gala) and sharing a few Instagram snaps of one another (like the rare kissing photo Kloss posted last month).

Although she has said she likes “having a more private life,” Kloss did confirm the engagement news on Instagram Tuesday by posting a sunset selfie with her new fiancé. “I love you more than I have words to express,” she wrote. “Josh, you’re my best friend and my soulmate. I can’t wait for forever together. Yes a million times over 💍.”

Kloss also told PEOPLE in 2013 that she appreciated that Kushner was “so not in fashion. It’s really refreshing to leave all the fashion shows and shoots and chaos totally behind.”

2. Joshua is a lifelong Democrat.

A rep for Joshua told Esquire in August 2016 that he was a lifelong Democrat and would not be voting for Donald Trump in the 2016 presidential election. Kloss has said she voted for Hillary Clinton.

Although he doesn’t share Jared’s political views, the younger Kushner has avoided commenting on his brother’s ties to President Trump.

Joshua told Forbes last year, “It is no secret that liberal values have guided my life and that I have supported political leaders that share similar values. But neither political party has a monopoly on the truth or on constructive ideas for our country. It’s important to be open minded and learn from differing opinions.”

3. He attended the Women’s March and March for Our Lives.

Joshua was spotted at the Women’s March in Washington, D.C., on Jan. 21, 2017, one day after Trump’s inauguration. Joshua reportedly told marchers that he was just “observing” the protest.

More recently, he joined Kloss at the March for Our Lives protest in March and then posted an Instagram photo of his now-fianceé holding a protest sign that said, “Load minds, not guns.”

Axios reported that Joshua also quietly donated $50,000 to March for Our Lives.

4. Joshua and Jared reportedly have a close relationship.

Despite their political differences, Joshua and Jared are said to be close, Newsweek reported in March.

Joshua told Forbes in April of last year that he and Jared “still speak every day,” but declined to elaborate on what they talk about or other aspects of their family dynamic.

Two days after Trump’s inauguration — and one day after attending the Women’s March — Joshua posted a captionless photo of him and his brother at the White House.

The brothers have also worked together professionally, co-founding a real estate technology firm called Cadre. (Joshua also founded his own investment firm, Thrive Capital, and a private health insurance company, Oscar Health.)

Jared told Forbes last year: “I’ve learned so much from watching Josh grow Thrive and observing how he thinks about investing. I’ve applied many of those key learnings to my businesses, and am working to bring more of that type of innovative private sector thinking to the government as well.”

5. Joshua is also reportedly close to Jared’s wife, Ivanka Trump.

They’re so close, in fact, that Joshua calls Ivanka his sister rather than his sister-in-law, Forbes reported.

Ivanka also embraced Kloss as her “sister” in an Instagram comment on Kloss’ engagement announcement.

“So, so happy for you and Josh!” Ivanka wrote. “I feel blessed to have you as a sister (!!!) Karlie and look forward to the decades of happy memories we will create together as a family!”

Ivanka also commented on her brother-in-law’s Instagram post about the engagement, writing, “So incredibly happy for you Josh. You and Karlie are blessed to have found one another. Here’s to a lifetime of love, laughter + adventure for you both!”