At least some of immediate family of Sam Bankman-Fried aren’t cooperating in the probe into the collapsed crypto exchange FTX and should be cross-questioned in court, the company’s lawyers have said in a legal filing made Wednesday.

The FTX founder’s brother, mother and father were his “advisors,” and should be subpoenaed alongside former company executives, as the company’s new management seeks to find what happened to allegedly misappropriated funds, the filing said.

“The Debtors and their advisors have been working tirelessly and nonstop over the last 70 plus days … to implement controls, recover and protect estate assets,” said the legal filing made jointly by FTX and creditor representatives. “Key questions remain, however, concerning numerous aspects of the Debtors’ finances and transactions," the filing continued.