Barack Obama gave his final speech as president Tuesday night in Chicago.
The two-term president thanked Americans for their support and offered support and encouragement for the future of the country, about which he said he's "even more optimistic" than when he took office in 2008.
During final remarks, Obama addressed his wife, whom he thanked for "(taking) on a role (she) didn't ask for" and making it her own "with grace and grit and style and good humor."
"You wore the burden of years in the spotlight so easily," he said. "Of all that I've done in my life, I'm most proud to be your dad."
Cameras panned to the elder Obama daughter, Malia, who sat teary-eyed beside her mother. But Sasha Obama was noticeably absent.
Social media users immediately took to the internet to question and speculate the younger Obama's whereabouts. Before long, the hashtags #WheresSasha and #WhereIsSasha started trending.
A senior administration official said the 15-year-old did not attend the speech because she had an exam Wednesday morning, CNN reported. The speech ended around 10 p.m. ET, and Sasha Obama would not have gotten back to the east coast until Wednesday morning.
Sasha Obama is a sophomore at Sidwell Friends in Washington, D.C. Her parents will be staying in D.C. after Obama's term ends so that she can finish high school.
Malia Obama is taking a gap year before beginning college at Harvard University in the fall.