The last of Nadya Suleman's octuplets is finally home with his brothers and sisters.

Jonah, who went home Monday night, was the smallest of the bunch, weighing just 1 pound 8 ounces when he and his siblings were born nine weeks premature.

The octuplets and their single mom, Suleman, who had six children at home before conceiving the eight, captivated — and in some cases angered — millions as the media chronicled their every move since their Jan. 26 birth.

Click here for photos of the octuplets.

But for both mom and children, the real challenge is just beginning, according to Dr. Manny Alvarez, managing editor of health for FOXNews.com.

Premature babies are at risk for a number of medical issues including hearing problems, speech delays, cognitive and learning deficiencies, and motor delays like cerebral palsy.

“These infants were premature, and this last baby stayed in the hospital for almost 12 weeks,” said Alvarez, chairman of the Department of Obstetrics and Gynecology and Reproductive Science at Hackensack University Medical Center in New Jersey. “There is a lot of data that has been published and analyzed looking at some of the hurdles that premature babies must overcome in their early years.”

For the parents of premature babies, keeping track of movement, visual, social and developmental milestones is the best way to identify potential problems and to find solutions to meet their babies’ needs, Alvarez said.

“Most premature babies meet their milestones and catch up by the age of 2,” he said. “But depending on how early an infant is born, their development may lag anywhere from 6 to 8 weeks in development, usually during the first year of life.”

Parents of preemies should use their child’s adjusted age when tracking development. For example, if the baby is 21 weeks old, but was born five weeks early, his adjusted age is 16 weeks (or 4 months).

While tracking progress, parents should not be afraid to ask for help from doctors, teachers or other family members, Alvarez said.

“I just hope that Nadya Suleman pays as much attention to their progress as she has to publicizing their births, because it should always be about the kids,” he added.

Click here to learn the milestones the American Academy of Pediatrics says babies should meet at 16 weeks and read Dr. Manny’s blog.

FOXNews.com's Jessica Mulvihill contributed to this story