Khalil Mohamed Atteya, known by his family as Niko, was thrilled at the thought of seeing the pyramids in Egypt with his mother, Kalliopi Atteya, and aunt Maria Panagos.
Police said Niko, his mother and aunt arrived July 30 at the Cairo airport.
Shortly after arriving in the country, Niko, 11, was separated from his mother and aunt, and he hasn't been seen since.
"This was a child abducted in a foreign county while on vacation with his mother. I find it incomprehensible," said Niko's uncle Perry Panagos of Fayetteville.
"It's gut-wrenching," said Niko's aunt Olga Panagos of Fayetteville.
"I think he's really going through a lot of stuff. I think he's probably crying every night. He just doesn't know what to do — he's scared," Perry Panagos said.
The Broadway Deli in Chambersburg, Pa., owned by Perry and Olga Panagos, has become somewhat of a command post in the quest to find Niko.
In the restaurant, several cellphones were strewn on the dining room table Tuesday, while another cellphone was being charged, as Olga jotted another name in her notebook containing an ever-growing list of government contacts.
"We've been in contact with basically every agency," Perry Panagos said, adding that the notebook was necessary in order to stay organized in the search for Niko.
Olga said the family even wrote letters to President Obama.
"This is a very serious matter to our family, and to the safety and well-being of our kid. This is a realistic kidnapping. Someone took Niko out of his environment and away from everything he knows," Perry Panagos said.
Niko recently completed fifth grade at Guilford Hills Elementary School, and is to begin sixth grade at Chambersburg Area Middle School-North later this month. Perry Panagos said his nephew is a typical boy who likes motocross bikes, playing basketball and video games.
Police are working with the U.S. State Department to find Niko, who went with his mother and aunt to visit his father, Mohamed Atteya, an Egyptian resident.
His father allegedly asked for the boy to visit his ailing grandmother in Egypt and attend his aunt's wedding, police said in a release.
On Aug. 1, a driver was transporting the boy's father and the group when he pulled over for what he claimed was car trouble, police said.
Pennsylvania State Police said Niko remained in the car while the others got out of it. The father got back into the car, followed by Niko's mother.
"As the victim's mother (got) back into the car, her ex-husband shoved her back out and ordered the driver to go, leaving the victim's mother and her sister along the road. They have not seen the victim since," police said.
Niko has been entered into the National Crime Information Center as a missing person, the Panagoses said.