The mother of former OpenAI researcher and company whistleblower Suchir Balaji, who died by suicide, is speaking out about the final days of his life.

In an interview this week, Suchir Balaji’s mother and father expressed confusion and shock over his sudden passing, expressing doubt their son could have died by suicide, as determined by the county medical examiner. The family hired an expert to perform an independent autopsy, but has yet to release the report’s findings.