The fates of the pilot, Lt Muath al-Kaseasbeh, and Japanese journalist Kenji Goto, previously had been linked.
The video of the beheading made no mention of the pilot, raising fears for his life.
"We want the government to tell us the truth," said Yassin Rawashda, an uncle of the pilot.
He said the family is not demanding a full briefing, but wants to hear if release efforts are headed "in a positive direction or not."
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"Of course, I'm concerned," he said by telephone. "This is my son. I'm always concerned about him and any development makes me more concerned."
Jordan is reportedly conducting indirect,behind-the- scenes negotiations through tribal leaders in neighbouring Iraq.
Last week, Jordan offered to release an al-Qaida prisoner from death row in exchange for the pilot, but the militants didn't say at the time if they were considering such a deal.
An audio message last week, purportedly from the Islamic State group, only said the pilot would be killed if the prisoner, Sajida al-Rishawi, was not delivered to the Turkish border by Thursday.
Al-Kaseasbeh was captured in December when his F-16 crashed near the de facto capital of the Islamic State group.
The militants control about a third of both Syria and neighbouring Iraq in a self-declared caliphate.
Jordan, a staunch Western ally, is part of a US-led military coalition that has carried out airstrikes against Islamic State group targets since September.
King Abdullah II says the campaign against the extremists is a battle over values, but participation in the airstrikes is not popular among Jordanians. The hostage crisis has prompted more vocal criticism of the government position.