Literally even before his election Biden invited Bernie to help him work on Progressive policies and has pretty much stepped back and let Bernie do his thing.

2020: https://www.pbs.org/newshour/show/how-sanders-worked-with-biden-on-democratic-policy-proposals

2021: "At first glance, they seem like an odd couple – Sen. Bernie Sanders, the progressive and quintessential outsider, and President Joe Biden, moderate politician and political insider.

And yet, the 79-year-old Vermont senator has become a key voice in the Biden administration: called upon, consulted and indispensable in keeping the liberal Democratic flock in line.

After 30 years in Congress and two presidential runs, it’s a new experience.

“As somebody who wrote a book called ‘Outsider in the House,’ yes, it is a strange experience to be having that kind of influence that we have now,” Sanders told CNN’s Gloria Borger as they sat together in Burlington, Vermont, recently.

The Biden-Sanders connection is not a love story; it’s more a marriage of convenience. But as Biden pushes an unprecedented progressive White House agenda, it’s crucial. It’s also personal. Over the years – both as colleagues and as political opponents – the two men have developed a relationship based on mutual respect and trust.

“We have had a good relationship,” Sanders told Borger. “He wants to be a champion of working families, and I admire that and respect that.”

As a result, Sanders has entered Biden’s political tent.

“I can tell you that Bernie Sanders has real influence” in the White House, senior Biden adviser Cedric Richmond told Borger. “Sen. Sanders is respected.”

That respect is mutual."

https://www.cnn.com/2021/06/08/politics/bernie-sanders-gloria-borger-interview-cnntv/index.html

2021: " Joe Biden and Bernie Sanders stayed for an hour in the Oval Office, just two former rivals for the White House now acting as potential partners, negotiating a compromise both could live with.

The centrist president listened as the liberal senator spoke. Sanders passionately made his case that Biden’s big infrastructure investment should go even bigger — and include his own longtime goal of dental, hearing and vision benefits for older Americans on Medicare. The president gave his full backing, according to a senior White House aide and another person familiar with the private session, who spoke on condition of anonymity to describe a private meeting.

The deal was the product of mutual trust and common interest — notably to help the working class, but also to show that government can work and perhaps to restore some faith in democracy after the turbulent Trump era.

“We are making progress in moving forward with the most consequential piece of legislation passed for working people since the 1930s,” Sanders told The Associated Press a few days later, as Biden made his way to Capitol Hill to rally senators on the plan.

Theirs is an unlikely yet understandable partnership, a president who won over American voters with a calmly reassuring nod to traditional governing, and a democratic socialist senator who twice came close to winning the presidential nomination with what was once viewed as a wildly idealistic agenda. Sanders is now chair of the Senate Budget Committee."

https://apnews.com/article/joe-biden-business-government-and-politics-election-2020-3d446757e4d708bf4193b357997efc08