You can also get rid of just the name part:
.legacy-name b {display: none;}
I think this would be okay as long as you're not intentionally misrepresenting what the legacy name is - for example, you can't replace it with a different name in the coding, and you'd want to be careful to change it back if you ever changed the pet's name so that it didn't just say "legacy name" if that wasn't actually true.
[Edit]Playing with it more I've found a way to get rid of the colon as well:
<style>
.legacy-name b {display: none;}
.legacy-name::after {content: ":"; color: ; margin-left: -7px; font-weight: bold;"}
</style>
So at least now you have that option. :)
If I have the original pet with a name I want it to be visble but I agree with . The way it is written sounds weird. 's suggestions would be better. I was also thinking I might like it if it said "The original (Insert Pet Name)".
I agree it's kind of awkward the way it is now. Something simple like legacy name or legacy pet would look better imo.