Actor Chris Pratt shared the emotional journey he experienced after his son's premature birth during the March of Dimes Celebration of Babies on Friday.

Pratt and his wife, actress Anna Faris, welcomed son Jack two years ago, and he was nine weeks early.

Jack weighed just three pounds and 12 ounces when he was born, and stayed in the neonatal intensive care unit for about a month. Pratt discussed the time he spent holding his son in the hospital.

"I made promises in that moment about what kind of dad I wanted to be and I just prayed that he'd live long enough that I could keep them," he revealed to Variety.

"I've done all kinds of cool things as an actor — I've jumped out of helicopters and done some daring stunts and played baseball in a professional stadium, but none of it means anything compared to being somebody's daddy."

The celebrity couple was told that Jack may have special needs and require surgery, but said their son is doing well.

"Our Jack went from a small, helpless little squirt to a strong, smart, happy, funny, beautiful boy who loves monster trucks and 'Daniel Tiger,' and, believe it or not, loves vegetables," Pratt shared. "Broccoli and cherry tomatoes are his favourite foods."

He also thanked the March of Dimes for their dedication to improving the health of babies and mothers.

"None of what we went through would be as easy even 10 years ago," the "Guardians of the Galaxy" star admitted. Life or death in the NICU is "a balance that's tipping towards life by cutting-edge medicines, much of which is a direct result of this wonderful organization, the March of Dimes," he continued.

The star-studded luncheon was also attended by Elizabeth Banks, Selena Gomez, and Steve Carrell, and many other celebrities, and raised over $1 million for the nonprofit.