Do tears have sounds?

1) "she realized that the sounds she kept hearing were not tears but suppressed"?
Well, sobbing has sounds, but tears are quiet always. So I failed get the logic of the expression: sounds...(of) tears... unless the "tears" here means something else.

Context:

Maria was born in Moscow, Russia and came to the United States when she was four years old. Her first ever book was written in Russian. It was five pages long and had something to do with trolls. When Maria was in fourth grade, she wrote a play. It took what felt like years to complete and all of fifteen minutes to perform. The audience (of proud parents and siblings) raved. Maria cried when she realized that the sounds she kept hearing were not tears but suppressed—and then not so suppressed—laughter at the dead king who couldn’t stop wriggling as he lay on top of the two chairs that were supposed to symbolize his tomb. You know how the story ends. The chairs slid apart. The deceased monarch crashed to the floor. The room erupted. It was not how Maria had envisioned her first theatrical production.
MOre:
http://www.mariakonnikova.com/about