Simplify the following text for a Grade 5 native English-speaking person.
Original: The Polish family appears and Aschenbach determines that they must not find out about the cholera outbreak for fear that they will leave . Aschenbach follows the family to a cafÃ , where the mother notices him and moves herself in between Aschenbach and her son .
Simplified: Aschenbach does not want the Polish family to leave Venice .