By Courtney Gousman
St. Louis (KSDK) - A 5-year-old boy with a serious heart condition is still missing.
Police are calling this a parental kidnapping and say he was taken from St. Louis Children's Hospital after he was discharged this afternoon. The child was in the custody of his mother.
PHOTOS - Porter Stone, Jeffery Stone, Rhonda Matthews
Relatives say the child's mother has legal custody of Porter Stone, but his father, Jeffery Stone, who now lives in California, came to town to check on his son.
Doctors say Porter's heart has been deteriorating for some time, and things could get worse since it's believed the child only has enough medication to last him through Wednesday afternoon.
Doctors at Children's Hospital say Porter was recently diagnosed with Cardiomyopathy, and has been going back and forth between St. Louis and Kansas City for treatment.
"His heart muscle is not pumping properly," said Dr. Sessions Cole, Chief Medical Officer of St. Louis Children's Hospital.
Hospital staff says Porter checked into Children's Hospital Friday.
On Tuesday his family made the decision to place Porter on a heart transplant list.
Porter had been discharged from the hospital at 3:50 p.m. Tuesday when investigators say he and 33-year-old Jeffery Stone disappeared.
"After the discharge, the father took the child to the pharmacy and the mother went to get the car."
Police say Porter's mother waited for her son and Jeffery Stone to show up, but they never did. She then called police.
Investigators say Jeffery Stone's mother, Rhonda Matthews, is also with the pair. Relatives say she drove in from California a few days ago.
Ian Fife, Porter Stone's maternal uncle, says Porter's parents are in the midst of an ugly divorce and custody battle.
"I believe it's to try and hurt my sister. To try and take control of the situation since he had no custody of the children," said Fife.
Doctors are concerned for Porter's health since at the time of his disappearance he was hooked up to a portable IV, which had about 24 hours worth of medication left.
"His heart function, which is already compromised, will begin to deteriorate, so as with any patient whose heart is failing, he would begin to breathe rapidly," said Dr. Cole.
Fife says Jeffery Stone had been very critical of his son's care during Porter's stay at Children's.
Jeffery Stone and his mother, Rhonda Matthews, were last seen in a silver or black Toyota Corolla with California license plates, 6BMU445.
If you have any information on their whereabouts call 911.