Chris Pratt speaks onstage at the March of Dimes' Celebration of Babies: A Hollywood Luncheon at the Beverly Wilshire Hotel on December 5, 2014 in Beverly Hills, California. Credit: Alberto E. Rodriguez/Getty Images

Sexy and sensitive! Chris Pratt got vulnerable for a good cause this past weekend.

The Parks and Recreation actor, 35, took the stage at the Beverly Wilshire Hotel in Beverly Hills, Calif., on Friday, Dec. 5, to speak at the March of Dimes Celebration of Babies Hollywood Luncheon. Pratt took inspiration from his own experience for the charity event.

The hunky star opened up about the premature birth of his son Jack, whom he welcomed with wife Anna Faris in August 2012. The little tot was born nine weeks early and weighed just three pounds at the time of his birth. 

"We were ready, we had been trying, and we were thrilled," Pratt told the crowd at the star-studded event of finding out that his 22 Jump Street star wife, now 38, was pregnant. "We were going to have a boy. My son — who was this guy going to be? What would we name him?"

Pratt and Faris soon settled on the name Jack, a tribute to Faris' father, and waited eagerly for their first child's arrival.

"Our little Jack didn't want to be an October baby," Pratt continued, hinting at his son's early arrival. "He wanted to be born in the summer, I guess. Anna woke me up in the middle of the night and she told me that her water had just broken. It was two-and-a-half months early. Oh, baby. Ready or not." 

The Guardians of the Galaxy actor then explained that the doctor wanted Faris, who was stabilized and monitored, to try to wait 30 days before having the child. Staying in the hospital, she kept busy with books, foot rubs from Pratt, and Mad Men DVDs. "Thank you, Jon Hamm," Pratt joked. "If we hadn't already named him Jack, we would have named him Jon Hamm." 

Finally, Jack couldn't wait any longer. 

"Then he came," the star explained. "Just about nine weeks early. He was three pounds, 12 ounces. Anna got to hold him for a moment and then it was off to the NICU — the neonatal intensive care unit. Three pounds, 12 ounces. That's a decent size bass. Very small for a human. He would need a lot. He had jaundice, so they put a blindfold on him and he slept beneath [a] creepy light and he had a PICC line, which is an IV that runs up his arm into his heart. He had a feeding tube and just wires in and out, and he lived in that incubator. That was his first crib."

 

"He was hooked up to these monitors and to us it meant that the machine started beeping because he stopped breathing over and over," Pratt added. "One of the brave and amazing nurses would come over and shake him a little bit, I guess to remind him he was alive. The only people allowed to touch him were his mom and me, unless you were wearing gloves. We did this amazing thing they call 'skin-to-skin' — it was just the best feeling I ever had. It's just what it sounds like. My little boy was laying across my neck and chest feeling my heartbeat and feeling my love, and I played him country music and I sang to him and I made him promises… in that moment… you know, about… just about what kind of dad I wanted to be, and I just prayed that he'd be here long enough and he was going to let me keep him."

Pratt's "tough as nails" kid made it through, and he and Faris got to take their son home when he reached four pounds, five ounces. 

"Our Jack went from a small helpless little squirt to a strong, happy, funny, and vocal boy," Pratt said. "He loves monster trucks and Daniel Tiger and, believe it or not, he loves vegetables. Broccoli and cherry tomatoes are his favorite foods," Pratt said, going on to explain his ties to March of Dimes, which works to support babies. "None of what we went through would have been as easy even 10 years ago, and much of that ease is really the direct result of funding from March of Dimes. We were lucky." 

"I've done all kinds of cool stuff as an actor," the box-office heavyweight added. "I've gotten to jump out of helicopters and do daring stunts and play baseball in a professional stadium, but none of them mean anything compared to being somebody's daddy."