Well, cell division is... regulated by structures called telomeres, for hominids in my multiverse. Telomeres essentially "cap off" the ends of chromosomes; aging somatic cells have steadily-shortening telomere caps. It is theoretically plausible that cells with telomeres of an infinite length, or some structure that replaced the f-functionality of them, might never age and undergo cytokinesis.

[Physically aging only due to starvation...? All of this makes Robert wonder about Cheyenne's biochemistry.]

Your species has... a d-decidedly fascinating biochemical composition.