In a desperate attempt to save her 4-month-old son's life, San Francisco mom, Lisa MacFarland, is reaching out to the public in hopes of finding a liver donation for her baby boy.

The single mother of two children, Kingston, 4 months, as well as another son, 2 years, says right from birth, Kingston hadn't been putting on much weight. Born at 6lbs 6oz, MacFarland, 36, says he was gaining about 4 ounces per week when typical newborns gain 0.5-1 ounce per day.

Despite feeding Kingston breastmilk and supplementing with formula, week after week the numbers on the scale didn't change much. Reaching out to Kingston's pediatrician, MacFarland says she was told to "continue the intense feedings and come back in about six weeks." Still, week after week, Kingston's weight barely shifted.

When the doctor noticed Kingston's abnormally low weight gain, a chest X-ray, ultrasound and blood work were done. MacFarland says that "his liver labs were slightly elevated, but the pediatrician didn't have a reason to be super alarmed." After checking over the results again, MacFarland got a call that she needed to be at UCSF Benioff Children's Hospital as soon as possible.

Ranking best in the nation, MacFarland knew she was in a good place but she continued to wait anxiously after more and more tests were done on little Kingston. Finally, doctors at UCSF diagnosed baby Kingston with a rare liver and bile duct disease: Biliary Atresia.

In an attempt to buy time, Kingston underwent a Kasai Procedure in June which supposedly can improve both bile flow and overall liver functioning. Whether or not the procedure was a success cannot be determined until late September but it isn't looking good.

With the need for a liver transplant in his near future, doctors worry that Kingston is only 13lbs when the 'safe zone' for transplantation is 20lbs. Not only that but to give Kingston the best chance, he would need a living donor- someone who would donate a lobe of their liver.

Dr. Emily Perito, the Assistant Medical Director of Pediatric Liver Transplants at UCSF says that in order for Kingston to get bumped up on the transplant list for a deceased donor, he has to get sicker. "Having a living donor means that he wouldn't have to be sicker, he can grow bigger, and they can schedule a transplant for the optimal time for him before he gets too sick," says his mother.

To see if you're a potential match and can help baby Kingston, visit ucliverdonor.org (Kingston's birthdate - April 13, 2019 - will be asked). To donate money, visit his GoFundMe page.

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One of the important things to remember if you're considering helping to save his life is that after a live liver transplant, like the one Kingston needs, your liver grows back. UCSF is also one of the best places to have it done.