Baby finally goes home after 135 days in NICU

Elaine Lewis was born April 9 at 1 pound, 4 ounces.

— -- A baby born prematurely was finally able to go home Tuesday after spending 135 days in the neonatal intensive care unit in Dallas, Texas.

Rachel and Bryan Lewis had been trying to have a baby for years, suffering two miscarriages in 2015 and 2016.

When they discovered they were expecting their daughter Elaine Marie, whom they call Lainey, after undergoing a fertility treatment called intrauterine insemination, they were thrilled.

"Lainey is our rainbow baby," Rachel Lewis told ABC News.

The new mother said "it was a fairly normal pregnancy," until her water broke on March 31 at only 22 weeks and five days. Rachel Lewis, 25, said she was put on "completely horizontal" bed rest for 10 days before doctors decided to induce labor at 24 weeks. Lainey was born weighing 1 pound, 4 ounces.

"The past five months we've been in fight-or-flight mode," Rachel Lewis recalled of having a premature baby. "We're powering through it ... when you're in that situation, you do what you have to do to get your baby out of the hospital alive with you."

Since then, Lainey has undergone three surgeries, her first at 5 weeks old to close a hole in her aorta. She's also had surgery to prevent retinal detachment in her eyes and to install a gastrostomy tube, or G-tube, in her stomach to aid with feeding.

"This whole experience has been real hard to wrap my mind around," Rachel Lewis said.

Rachel Lewis and her husband of three years got some good news "a couple weeks ago," she said, when they were told they'd be able to take Lainey home after more than four months in Medical City Children's Hospital in Dallas.

“Our team of physicians, nurses and caretakers were honored to care for Lainey in the Medical City Children’s Hospital NICU,” Bill Lee, CEO of Medical City Children’s Hospital, told ABC News in a statement. “Our goal is to return these fragile infants to good health. We are thrilled that Lainey got to go home to her family as a healthy and happy baby.”

The two turned it into a joyous occasion for Lainey, inviting both of their families to their home in Richardson, Texas, on Tuesday.

In fact, their families have been instrumental to the couple by donating money, mowing their lawn, dropping off meals and even planting flowers in their garden "because they knew we couldn't keep up with it," Rachel Lewis said.

The new mom said she and her husband were "giddy" when bringing their now-8-pound baby home.

"We're just really happy. We're elated. That's a good word for it," Rachel Lewis added.