Who did what to Who?? in this sentence.

[gxiang]

i've just read this sentence, and feel confused at who did what to who?

she feared they would victimize her for squealing on their pals.
(note:i've checked that squeal here means :inform on someone to the police or a person in authority)

[Casiopea]

Try this:

Mary feared John and Sam would victimize Mary - because Mary squealed on John and Sam's pals.

[gxiang]

yeah, i understand now. thank you! :)