Barack Obama and Joe Biden threw a joint party to celebrate women in their family graduating high school

Alex Wong/Getty Images

Joe Biden and Barack Obama.

• Barack Obama and Joe Biden got their families together to celebrate the women in their families graduating high school together.
• Biden said that his granddaughter Maisy Biden and Obama's youngest daughter, Sasha Obama, are close friends, and that the two families "had a whole get together."
• Biden, who is now running for president, and Obama have a well-documented friendship, and in 2016 Biden called Obama a "brother to me, a best friend forever."
• Biden said that the graduation was why he missed a Democratic event for 2020 candidates in Iowa: "My granddaughter was graduating. It was my daughter's birthday. I would skip inauguration for that."

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Joe Biden said that he and former President Barack Obama threw a joint party to celebrate the women in their families that were graduating high school together.

Biden, who served as Obama's vice-president between 2009 and 2017, told reporters on Tuesday that he and Obama brought their families together.

They were celebrating his granddaughter Maisy Biden and Obama's daughter, Sasha Obama, graduating from the same high school.

The two have a well-documented close friendship, and he said that the two women are close.

"[Maisy's] best friend is Sasha Obama. Barack and Jill and the whole family, we had a whole get together," he said, according to The Hill.

Read more: 44 pictures of the incredible bromance between President Obama and Vice President Biden

He said that the party was why he missed a Democratic event in Iowa on Sunday as he runs to be the Democratic presidential nominee.

REUTERS/Jason Reed

Sasha Obama and Joe Biden in the East Room of the White House in May 2009.

Andrew Yang, one of Biden's Democratic competitors, noted Biden's absence, telling reporters: "I thought the same thing you all did, which is this: Joe Biden must really not like to travel."

Biden did not name Yang on Tuesday, but said: "One of my competitors criticized me for not going to Iowa to talk for 5 minutes."

"My granddaughter was graduating. It was my daughter's birthday. I would skip inauguration for that."

AP Photo/Javier Galeano

Joe Biden with his granddaughter Maisy Biden and grandson Nick Biden in Bogota, Colombia in June 2014.

19 Democratic candidates spoke at the Iowa Democratic Hall of Fame dinner. Some took the opportunity to criticize Biden and his desire to find a middle ground on a number of issues, but they did not name him.

Biden is attending a number of campaign stops in Iowa this week.

Read more: Biden is still leading in a 2020 Iowa poll, while Sanders, Warren, and Buttigieg are fighting for second place

Obama has expressed support for Biden but has not formally endorsed him. Biden told reporters in April that he asked Obama not to.

White House via Flickr

Joe Biden and Barack Obama have a well-documented friendship.

"I asked President Obama not to endorse," Biden said. "And he doesn't want to - whoever wins this nomination should win it on their own merits."

The two men appear to share a "bromance" that has been captured by photographers throughout the years.

In April 2016, for Obama's last birthday in office, Biden wished Obama a happy birthday by calling him "brother to me, a best friend forever" and sharing a picture of homemade friendship bracelets with each others' names on them.

Jill Biden, Biden's wife, also previously said that the two have a "truly beautiful friendship" and that "they really love one another."

Jill and Michelle Obama also appear to have a close relationship. Michelle said in 2016 that "Jill is not just brilliant, but she is kind. She is very funny, and she is one of the strongest people I know. I love and admire her with all my heart."