Lt. Jeffery Gray and daughter, Payton. (Credit: Lisa Fielding/WBBM Newsradio)

CHICAGO (CBS) — It was business as usual inside Mrs. Clancy’s fourth grade math class at Newberry Math and Science Academy until Lt. Jeffery Gray walked into the room.

“Hey, Payton,” he said.

“Dad?” she replied.

There wasn’t a dry eye in the room as Gray gave Payton a surprise of a lifetime.

He just returned from an eight-month tour in Afghanistan.

“I’ve been in the U.S. Navy Reserves for 20 years,” he said. “This was my first and last tour of duty.”

There wasn’t a dry eye in the room as Payton clung to her dad crying.

“I’m so happy you’re home,” she said.

“I’m home to stay, it’s OK,” reassured Gray.

Payton says she had no idea her dad was back.

“I thought he was in Virginia and I didn’t think he was coming home until next week.”

Payton’s parents thought it would fun to surprise her but admit they didn’t know what to expect.

“I wasn’t sure I could keep the secret. She had no idea,” said Kathy Gray, Payton’s mom. “She was ready for him to come home.”

The first thing she wants to do with her dad now that he’s home to stay?

“Go shopping,” said Payton.

“I better get out my wallet,” laughed Gray.

Lt. Gray says they communicated through Skype and through photos and email but today’s a day he and his daughter will never forget.

“She’s definitely a daddy’s girl,” he said.