Sasha Obama, right, and Malia Obama, laugh during the National Christmas Tree Lighting ceremony in Washington on Dec. 3. (Carolyn Kaster/AP)

It was one of the more emotional moments of President Obama’s farewell address. His eyes swelling with tears, he spoke of his wife, “Michelle LaVaughn Robinson of the South Side,” and then, of his pride in their two daughters, Malia and Sasha.

“Under the strangest of circumstances you have become two amazing young women,” Obama said. “You are smart and you are beautiful. But more importantly, you are kind and you are thoughtful and you are full of passion.”

“And,” he added, pausing for applause, “you wore the burden of years in the spotlight so easily. Of all that I have done in my life, I am most proud to be your dad.”

When his family joined Obama on the stage, at the close of his farewell speech, they held hands and waved at the audience, creating an image of the family that mirrored a similar one from more than eight years ago, at Obama’s victory rally in the same city. But one member of the family was missing: the youngest, Sasha.

President Obama paid homage to the first lady, his daughters and Vice President Joe Biden during his farewell address in Chicago. "You have made the country proud," he said to his wife as he wiped away tears. (Victoria Walker/The Washington Post)

And immediately, the Internet noticed. People tweeted in confusion, wondering where the teenager could be.

What could possibly be more important than seeing her father’s parting address? They asked and hypothesized:

https://twitter.com/dorantesmarisol/status/819017767575834624

Soon enough, the answer arrived. She had an exam at school Wednesday morning, a White House official said. While her family traveled to Chicago, Sasha stayed in Washington.

The 15-year-old attends Sidwell Friends, a highly selective school in the nation’s capital. On the school’s website, exam protocols include guidelines that “students must adhere to the published examination schedule. Absence for travel is not an adequate reason to re-schedule an exam.”

Even, perhaps, if the travel is for your father’s presidential farewell address?

It is not the first time that Sasha’s academic commitments have made headlines. In March, Obama announced that he and his family will stay in Washington for a couple of years after his presidency so that Sasha can finish high school.

“Transferring someone in the middle of high school — tough,” the president said.

This post has been updated.

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