Sgt. Bergdahl’s father, Robert Bergdahl, emerged as a fierce advocate for his son during the five years that Sgt. Bergdahl was held in Pakistan by the Haqqani Network, pushing for action to get his son released. When Sgt. Bergdahl was released to U.S. Special Forces following a prisoner exchange that freed five Taliban detainees held at Guantanamo Bay, Mr. Bergdahl and his wife appeared at a White House announcement alongside President Barack Obama.

Since then the decision to trade Sgt. Bergdahl for the Taliban detainees has become deeply controversial.

The family has put sharp restrictions on what information can be released about Sgt. Bergdahl’s condition and has asked the military not to give updates about communication between him and his family, according to another Army official.