A friend from Seattle just shared this with me.
Boy who touched Obama’s hair: Story behind White House photo is probably in your inbox (view link)
In May 2009, the child, Jacob Philadelphia, was visiting the White House with his father, a former Marine who was leaving his 2-year stint working for the National Security Council as part of the White House staff. The father asked to take a family photo with the president. Jacob said he had a question for Obama, who was then in his fifth month in office.
The Times recounts the rest:
"I want to know if my hair is just like yours," he told Mr. Obama, so quietly that the president asked him to speak again.Jacob did, and Mr. Obama replied, "Why don't you touch it and see for yourself?" He lowered his head, level with Jacob, who hesitated."Touch it, dude!" Mr. Obama said.As Jacob patted the presidential crown, ... [White House photographer Pete] Souza snapped."So, what do you think?" Mr. Obama asked."Yes, it does feel the same," Jacob said.