Gibbon appears fully matured by the time Charlie is in her fifties. He is born when Charlie is in her thirties. His fur is a brownish-gray, and is more shaggy than that everyone else in his family. Gibbon's jowl and eyes, or rather his face in general is identical to Jake's, much like Kim Kil Whan. He possesses a bushy tail, and his limbs appear to have no appendages.
- Gibbon is the second child of one of Jake's children to have been revealed.
- The father of Gibbon is unknown, and where the other half of his genes come from is unspecified.