One day at a time for Missouri family celebrating son's first and last Christmas

STRAFFORD, Mo. - For one family in Strafford, Mo., this holiday holds special meaning.

This will be their 5-month-old son's first and last Christmas.

Doctors diagnosed Logan Ruth with the deadly genetic disorder Spinal Muscular Atrophy, the most severe and most common genetic cause of infant death.

"We're just going to love him as much as possible while he is still here with us," Logan's mother, Tia Ruth, said. "Whenever he is gone, we are going to as much as we can to keep his memory alive."

Tia says her pregnancy with Logan was normal, until the third trimester.

"We started going to labor and delivery," Tia remembers. "It seemed like almost every other week because we wouldn't feel him move."

Doctors told her everything was fine, but as it turns out, those were warning signs.

"It was actually the SMA coming to light during that time," Tia said.

Spinal Muscular Atrophy is genetic, but the Ruths had no idea they carried the gene.

"We never heard of it before," Tia said. "There was nothing in our family lines that would indicate that we both would have the gene."

Infants born with the condition have very little muscle tone, weak muscles and feeding and breathing problems.

It wasn't until Logan turned 2 months old that it started to show.

"Then at two months it kinda went downhill to the point where he doesn't have neck control," Tia said. "He's not able to sit up straight. He doesn't move his legs, he wiggles his feet a little bit.

Doctors say Logan will die before his first birthday.

"Almost every day we have what we call a five minute morbid talk where we address something in regards to his death or it coming."

With Logan's time cut short, Mom, Dad, and big brother Lucas are making the most of what time is left.

Tia made her son his own bucket list. It included things from his first haircut to meeting Santa.

"It's just really important for us to kinda have those markers to look back upon and have all these memories especially for our older son as he's growing up and we look back on these times that we just have wonderful memories that we can revisit."