During his farewell speech Tuesday night, President Barack Obama thanked his wife, Michelle, and daughters Malia and Sasha for sacrificing for his political dreams -- but one of them was notably missing during the thank you.

Sasha Obama, the president’s younger daughter, was not in attendance during Mr. Obama’s final speech while in office. With no explanation about her absence, Twitter exploded with questions about why Sasha was not there.

But for real, where is Sasha Obama? pic.twitter.com/NmxOXkBBqp — Tammi LaTela (@TLaTela) January 11, 2017

I need to know, where is Sasha #SashaObama — Jennifer Levy (@Jlevycj) January 11, 2017

Though many pointed out it is a school night for the 15-year-old, some had other theories as to where she might be.

Sasha Obama:"Can I get Tuesday night off, my dad is giving his farewell speech"

Manager:"Only if you can find someone to cover your shift" — Celine Besman (@CelineBesman) January 11, 2017

Why isn't Sasha Obama at this speech? I'm just going to assume it's because it's a school night and Obama seems like that kind of Dad — Josh Billinson (@jbillinson) January 11, 2017

Lol y'all know Sasha Obama wasn't there because her mama isn't about to let her go out on a school night. — • K H A D E G A • (@TheKhadegaMo) January 11, 2017

Only 18-year-old Malia traveled to Chicago for her father’s speech.

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So where, indeed, was Sasha? CBS News correspondent Mark Knoller tweeted the answer as told to him by the White House:

Where was Sasha? WH Official says she stayed back in DC tonight because she has an exam at school tomorrow morning. — Mark Knoller (@markknoller) January 11, 2017

Mr. Obama said during the speech that both daughters “wore the burden of years in the spotlight so easily.”