In this Aug. 12, 2008, file photo, then Democratic presidential candidate Sen. Barack Obama, D-Ill. walks down Kailua Beach in Kailua, Hawaii, with his daughters Malia, 10, left, and Sasha, 7, during their vacation in Hawaii. President Obama spoke Friday at the White House about being a father, imploring dads everywhere to be involved in the lives of their own children.

Washington ? Growing up without a father left a hole in his heart, President Barack Obama told boys at the White House Friday in a remarkably personal Father’s Day weekend message. He implored fathers everywhere — and the kids when they’re older — to be involved in the lives of their own children.

“This isn’t an obligation,” said the father of two in a message to millions of wayward dads. “This is a privilege to be a father.”

Obama spent hours on Friday with teenagers, young men, community mentors and everyday dads in hopes of launching what he called a national conversation on responsible fatherhood. Each story was personal. But one of them commanded the most attention: his own.

He spoke at length about how his father, Barack Obama Sr., left home early. The future president was just 2 at the time and saw his dad only once more, at age 10, a short visit that still left a lasting imprint.

“I had a heroic mom and wonderful grandparents who helped raise me and my sister, and it’s because of them that I’m able to stand here today,” he told a throng of youngsters and leaders of community organizations. “But despite all their extraordinary love and attention, that doesn’t mean that I didn’t feel my father’s absence. That’s something that leaves a hole in a child’s heart that a government can’t fill.”

In candid terms, Obama said he promised himself he would not repeat his own father’s mistakes.

“Just because your own father wasn’t there for you, that’s not an excuse for you to be absent also. It’s all the more reason for you to be present,” Obama told the young men in his audience.

“You have an obligation to break the cycle and to learn from those mistakes, and to rise up where your own fathers fell short and to do better than they did with your own children,” Obama said. “That’s what I’ve tried to do in my life.”

An estimated 24 million American children are growing up with absent fathers, and a disproportionate number of them are African-American. Those children are at higher risk of falling into lives of poverty and crime and becoming parents themselves in their teenage years.

The White House is trying to tackle that problem, adding to its packed domestic agenda, but without seeking legislation or new policies. It is sponsoring forums around the country this summer and fall to promote programs for mentors and fathers and to see how the federal government can support them.

And then there is Obama’s personal attention. Only issues of special importance to a president get a full afternoon of his time.

Obama began with a visit to a nonprofit center that trains young men and women from urban backgrounds for high-tech careers or higher education; he later led the town hall in the East Room and then mingled with youngsters on the South Lawn as they chatted with other big names and got some lessons about life.

Danilo Downing, a 16-year-old who just finished his sophomore year at Yorktown High School in Arlington, Va., said the White House visit changed his life. He’s never met his father, and connected with the president’s comments.

“I think of him as my father now,” Downing said after he shook Obama’s hand and got a pat on the back. “He’s really special to me. He’s an amazing man.”

The president and his wife, Michelle, have two daughters: Sasha, 8, and Malia, 10.

“I’ve been far from perfect,” Obama said in measuring himself as a father. “But in the end it’s not about being perfect. It’s not always about succeeding. It’s about always trying. And that’s something everybody can do. It’s about showing up and sticking with it.”