Trent wears jewelry which is uncommon for pre-made Sims. While the jewelry he wears can be accessed in normal Create a Sim, but can't be accessed in gameplay, Trent's household has access to jewelry that can't be accessed in Create a Sim, even with debugging mode enabled. This can be proven by changing a member of the household's appearance. There is a mod which unlocks the vacation jewelry so that it can be accessed in normal Create a Sim.
Even though Trent has light blue eyes, his SimDNA in SimPE reveals that his genetics are for grey eyes. He and the other members of his family are some of the only Sims in The Sims 2 whose eye colors do not match their genetics. While it is very simple to change his genetics to match his eye color, it is much less simple to change his eye color to match his genetics, since it requires opening his character file, and changing multiple genetic codes.
Trent's face is a slightly modified version of a pre-made face from Create a Sim. The face is in the bin for adult males with light skin (skin tone 1), and has a blond mop top and glasses. This CAS face, if used on toddlers or children, has a shrunken chin and plump face.