By Mark Abrams

PHILADELPHIA (CBS) — The family of a Willow Grove man, who died of an accidental drug overdose a month ago after cooperating with authorities in a clergy sex abuse case, has filed a lawsuit against the Philadelphia Archdiocese and the man’s alleged abuser.

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Attorneys for 26-year-old Sean McIlmail’s family insist it’s not about the money, but the search for truth and justice for all victims of clergy sex abuse in the archdiocese.

His mother, Deborah, says the family is still trying to cope with his loss.

“Sean appeared good on the outside. But on the inside, he didn’t believe in himself,” she said. “The unspeakable, disgusting horrors that had happened to Sean by Father Robert L. Brennan would haunt Sean forever.”

Deborah McIlmail alleged the abuse by Brennan lasted four years, beginning in 1993 when Sean was 11 and attending Resurrection of Our Lord Parish school in Rhawnhurst.

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Days after McIlmail’s death last month, District Attorney Seth Williams reluctantly dropped the case against Brennan.

Brennan was labeled a serial sexual predator and mentioned in two grand jury reports about clergy sexual abuse in the archdiocese.

The suit also names Monsignor William Lynn, former secretary of clergy in the archdiocese, for failing to act to protect McIlmail.

Lynn is serving three to six years in state prison for his conviction for covering up clergy sex abuse while he served in his management role of priests from 1992 to 2004.

The archdiocese had no comment on the suit.

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