There are few relationships in the nation’s capitol as complex as that of the president and the vice president, which is a partnership that is forged by political necessity and defined often by competing self-interests and rivalry.

For President Barack Obama and his Vice President Joseph Biden, there has been some trying moments since the two took office over six years ago.

However, the recent death of Beau, Biden’s oldest son, has put the striking person bond between the president and vice president under the microscope, two men from different backgrounds and different generations.

Obama said during a deeply personal eulogy at Beau’s funeral that Joe you are my brother. He added that he was grateful every day for the big heart his vice president has and the big broad shoulders.

His voice could be heard cracking during his remarks, which was a rare display of emotion in public for a president who typically has a very cool demeanor.

Biden however is known to overflow with his emotions at even the most mundane event at the White House.

Obama is 53 and Biden 72, while their years in the Senate overlapped for a short period the two were never particularly close.

After he won the presidential nomination for the Democrats in 2008, Obama chose Biden to be his running mate partly hoping that 36 years of Biden experience would offset the inexperience in Washington he had.

Biden quickly took over tough jobs, once the VP, including policy on Iraq and economic stimulus, as well as Ukraine and gun control.

More than the policy or political skill, that Biden possesses, aides say that Obama is attracted to the closeness Biden has with his family. While the vice president’s family is very large as well as close-knot, Obama barely knew his own father and was raised by a single mother and grandparents.

One aide said that Obama is drawn towards the emotional power the Biden family has, the vice president’s intensity for commitment to his family and the same they have for him.

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