The day after the inauguration of President Donald Trump, while Jared Kushner was getting dressed for the Freedom Ball, his younger brother, Joshua, was photographed at the Women’s March on Washington.

The march, which was broadly anti-Trump, was the largest political demonstration since the anti-Vietnam protests in the 1960s.

Joshua, a lifelong Democrat, could not have chosen a more direct way to prove that he is no Kushner clone.

Last month, Jared was appointed a senior adviser to his father-in-law, Donald Trump, slipping into a role that makes him one of the most influential people in the United States.

Joshua, a venture capitalist, who at 31 is four years younger than his brother, looks the Kushner part: high-school-prom-handsome, dimpled, impossibly rich.

However, as a keen supporter of Barack Obama’s Affordable Care Act (ACA), which Mr Trump has committed himself to dismantling, Joshua’s politics are diametrically opposed to his those of brother.

One of Joshua’s most high-profile business ventures has been as co-founder of Oscar Health, an insurance provider designed to help Americans navigate the complex health system using digital apps. In a blog post shortly after the election, Joshua and his co-founder, Mario Schlosser, declared their continued support for the ACA, writing: “All Americans deserve healthcare coverage that is high quality and affordable.”

Despite their political differences, the Kushner brothers are reportedly close. Jared has sold many of his business assets to Joshua to avoid accusations of conflicts of interest when he accepted his White House position.

Growing up as Orthodox Jews, in Livingston, New Jersey, the Kushners have long been immersed in Jewish culture.

When Jared travelled to Poland as part of a March of the Living trip to Holocaust sites in 1998, the impact was powerful. “He was understanding the severity of our journey, the commitment he had to his family and his legacy,” said Joel Katz, who led the trip. He was “extremely steeped in Holocaust education and Yiddishkeit”.

Elisheva Ben Ze’ev, who was in the same group as Jared, described an incident which contrasted starkly with Mr Trump’s boast about sexually assaulting women. Jared, she told the Forward, defended her when she was grabbed by a stranger. Ms Ben Ze’ev said she was approached by an older man who tried to hug her. Jared threw him to the ground and shouted: “Don’t you touch her, get away from us”.

Marti Sichel, another participant, told the Forward: “He didn’t come off as a jerk like somebody might if they knew that all the girls on their tour are crushing on them.”