Presidents and Vice Presidents often are an awkward pair, with the Vice President chosen for electoral and regional reasons, not because of friendship or familiarity before the Presidential term.
Most Vice Presidents are ignored by the Presidents they are serving, and some have even, actively, worked against the President’s interests.
Most Vice Presidents, historically, have not been even considered as possible successors.
Often, the connection between Presidents and Vice Presidents are considered like a “shotgun marriage”!
Examples of awkward combinations are Thomas Jefferson under John Adams; Aaron Burr under Thomas Jefferson; John C. Calhoun under both John Quincy Adams and Andrew Jackson; Charles Fairbanks under Thedodore Roosevelt; Thomas Marshall under Woodrow Wilson; Charles G. Dawes under Calvin Coolidge; John Nance Garner under Franklin D. Roosevelt; Lyndon B. Johnson under John F. Kennedy; Hubert Humphrey under Lyndon B. Johnson; Spiro Agnew under Richard Nixon; Dan Quayle under George H W Bush; and Mike Pence under Donald Trump.
The greatest and most intimate team was Jimmy Carter and Walter Mondale, and their partnership lasted 45 plus years until Mondale died in April 2021. Carter made Mondale as close to a co-President as could be possible, as Mondale was in on every decision, and the two men and their wives were very close in office and for the 40 plus years of retirement together.
No other combinaton comes close, although Joe Biden under Barack Obama would rank second in closeness and intimacy.
Until the revelation of the personal scandals under Bill Clinton, Al Gore was also very close and intimate, but the Monica Lewinsky scandal created a barrier for the remainder of Clinton’s second term, causing Gore not to utilize Clinton in the 2000 Presidential race, a major factor in Gore’s defeat, despite winning the national popular vote over George W. Bush.
The extent of the closeness and intimacy of Kamala Harris with Joe Biden is not yet fully understood.