Investigators said earlier this week that Bravo bought a shovel and duct tape several days before Aguilar went missing.
Bravo was in the Alachua County jail on a charge of depriving a victim of medical care when police filed the murder charge.
Carlos Aguilar, Christian's father, said he had been in contact with Bravo's father until Thursday, but he said Bravo's father is no longer answering or returning his calls.
Carlos Aguilar said his family was going to the jail Friday to try to talk to Bravo themselves. They tried to Thursday, but Bravo denied visitation.
"I don't think it's fair that a person is missing and the only person with information to find him is protected by the Fifth Amendment," Carlos said. "That's ridiculous. We need to be able to have the authorities talk to people like that."
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