The 35-year-old vanished last week after his empty 31-foot fishing boat washed up on a Fort Lauderdale beach with the engines still running, ABC News reported.
Since then, Aguiar's mother, Ellen, and his wife, Jamie, have engaged in a legal tug of war over who will take control his estate.
In a new court document, Jamie Aguiar, 35, accuses her mother-in-law of being incapable to handle the estate.
Aguiar's mother filed documents saying her son may be alive and in a "delusional state or be suffering from psychosis."
Her attorney, Richard Baron, told ABC News that an hour before Aguiar got on his boat his wife told him she wanted a divorce.
"I'm of the belief that that's what pushed him over the deep end," Baron said. "He loved his wife. He did not want a divorce."
A Broward County court is scheduled to take up the matter of conservatorship Thursday.