Parsha Question

In shemos perek 2 posuk 11 it says Moshe hit a Mitzri who was hitting a Jew from his brothers:
מכה איש עברי מאחיו
The שערי אהרון says that אחיו literally refers to a Jew from Moshe’s family, someone from קהת. The question is: why was someone from קהת in the slavery if שבט לוי was exempt from the slavery?
The שערי אהרון doesn’t answer the question.
Does anyone know?

1 Like

Great question. Did you find an answer? Curious to know what is the Shaarei Aharons rayah that it was from his family?