Bibu is a 4-year-old the second born triplet, and the eldest son. Although not in the Disney version, the father is shocked to see his "just a little yellow guy with a big tail", but dispite the crying, the father and son bond was strong enough for that to not matter, as Bibu is his little yellow guy. Though learning to defend himself, Bibu is accident prone and hurt himself (or got into situations that could've got him hurt) numberous times, and it's up to the rest of the family to help. When left in the care of someone else (Hector, the Marsu-Sitter) he cries, not just in hunger or boredom, but mostly just because he misses his parents while his brother and sister are more understanding... this indicates he's sencitive.