The youngest of the soccer players rescued from a cave in northern Thailand put his hands together to gesture "hello" when he realized his parents stood on the other side of the hospital's glass partition.

The family of 11-year-old Chanin Viboonrungruang and other relatives were finally able to glimpse the boys through protective glass on Wednesday -- one day after the conclusion of a complicated three-day operation to extricate them. This was as close as they would get since sending the boys off to soccer practice last month.

The team had become trapped on June 23 when rising flood water trapped them deep inside the cave. Their ordeal made headlines around the world.

"I started to cry, everybody started to cry," his exhausted father, Tanawat, told CNN in an exclusive interview after seeing his son.

"I want to say thanks to those who rescued my boy. And helped him to have a new life, it's like a rebirth."

Viboonrungruang hadn't seen the boy in nearly three weeks. They spent their last night together watching a World Cup match. Now tears streamed down his father's face. Chanin's mother shouted his name and the words "Sou Sou," a Thai term of encouragement.

"I was so happy in that moment," the father said of seeing his son in the carefully controlled hospital environment where the boys will remain for seven days.

He was not alone. Other parents waved and wept as their sons signaled "I love you" from the beds.

For weeks, parents had maintained a constant vigil outside the cave where members of the Wild Boars soccer team and their assistant coach were trapped.

The vigil now moved to the hospital, where family members watched from behind the glass divider to avoid infecting the boys.

"As long as I get to see him alive and healthy, I am OK with that," Viboonrungruang said.

Chanin mustered the strength to turn to his parents. He raised his hands above his head to greet them. He wiped tears and managed a wave.

Viboonrungruang said he was grateful to see his son's face and relieved that he was healthy except for a slight fever.

But he's still desperate for the moment when he can just hug Chanin, finally feel like he can touch and protect his son again, who is known by his nickname Titun.

"I get to wave at him," Viboonrungruang said. "He was weak but he turned around and waved and, in the beginning, we told him ... "You can get through this. We will come to visit every day. We will wait for you. Don't worry about anything at all."

Health ministry inspector Tongchai Lertvirairatanapong said the boys were in "good condition," despite each losing an average of two kilograms (4.4 pounds) in weight during their time in the cave.

During the hours-long and perilous rescue, each boy was accompanied underwater by two divers who helped them navigate the dark, murky water. The most dangerous part was the first kilometer, during which the divers and boys were required to squeeze through a narrow, flooded channel.

Chanin was the last boy to come out, followed by the coach. He watched his friends rescued one by one for two days, patiently awaiting his turn.

Viboonrungruang said the parents drew strength from all the people who stepped up to help and lend their support.

"Just think that all of these people are trying really hard to help us," he said. "We have to stay strong. ... They didn't let fear take over. They stay hopeful because we are in it together from the first day to the last day."

During the ordeal, Chanin's younger brother thought the boy was away playing in a cave, their father said. His brother imagined a fairytale story of a mountain, with Chanin away on a long journey.

"I am sure that he missed his older brother," their father said. "He just asked, 'When will he come out?'"

When the 12 boys sent letters to their parents before the rescue, Titun wrote that the prospect of a tasty fried chicken meal was foremost in his mind.

The letters were posted on Facebook by the Thai Navy SEALs who led the evacuation effort that involved pulling the boys through four kilometers (2.5 miles) of narrow, dark, twisting and flooded tunnels.

"Dad, Mom don't worry about me," Titun wrote. "I am fine. Please tell Pee Yod (older female relative) to take me to eat fried chicken. Love you all."

His father said his wish will be granted, but that the family also wants to carefully evaluate Chanin's feelings and state of mind.

"I think that this will be a lesson for him," Viboonrungruang said. "I believe that this will help him in a good way."

Viboonrungruang's cousin drew a sketch of the the former Thai Navy Seal, Saman Kunan, who lost his life during the rescue operations. It is encircled by 13 messages from each of the families. Chanin's family wrote, "Sam is our hero for our family forever. We will not forget."

Knowing his kind and gentle son, Viboonrungruang said he believes Chanin will feel guilty and apologetic. Viboonrungruang also was apologetic to all those who sacrificed their time and effort for the boys.

"I will teach him to grow up a good person and help society," he said of his son. "And I will let him follow his dreams."

CNN's Arwa Damon, Patrick Sarnsamak, Sandi Sidhu and Abeer Salman reported from Thailand, Ray Sanchez wrote from New York.