3 Stacks Smoke and Tap House in Frisco, Texas treated doctors at Massachusetts General Hospital to a barbecue lunch, April 23, 2013, a thank-you for sending pizza and an encouraging note to Hillcrest Hospital, which treated 28 patients after the Texas fertilizer plant explosion. (Credit: Courtesy 3 Stacks Smoke and Tap House)

It all started when Dr. Chris Kabrhel, an emergency room physician at Massachusetts General Hospital in Boston, sent pizza to the Hillcrest Hospital staff members in Waco, Texas, to thank them for their hard work after the fertilizer plant explosion that killed 14 people and injured hundreds of others 20 miles away in West, Texas.

Kabrhel sent the pizza to Texas Friday night even though his own hospital had received 29 Boston marathon bombing victims earlier in the week and were working with a smaller staff Friday because of the citywide lockdown that continued till the early evening.

"Thanks for all of your hard work," the handwritten note says in black marker. "From one member of the E. R. family, Chris Kabrhel - Mass General Hospital."

When Trace Arnold, who owns a newly opened barbecue joint, heard about it, he decided to return the favor - Texas style.

"For the medical staff in Boston to be so thoughtful in the middle of their own city's tragedy and think about us down here in Texas was just awesome," Arnold said in a statement.

Courtesy of his new restaurant, 3 Stacks Smoke and Tap House in Frisco, Arnold flew about five coolers of ribs to MGH today. It arrived along with a giant, green Hillcrest Hospital flag that had been signed by 300 hospital employees offering words of encouragement.

"Literally, you can't believe," Dr. Paul Biddinger, who directs emergency operations at MGH, said as he spoke to ABCNews.com just before tucking into a plate of ribs. "You can't believe the smiles on our staff's faces right now."

Five bomb victims remain at MGH. Of the 28 patients admitted to Hillcrest Hospital on the Wednesday after the plant explosion, 24 have been discharged.