Companion's re-use time

Hello, i need some help to fix something.

First, sorry if this isnt the correct place to answer.

My problem is that i want to “create” a companion, that only can be used each few hours. The compaion is Argent Gruntling ( The problem with it is that, you can summon as many times as you want, but the time without re-used it, must be the same. In this case, 4 hours. So, i need the companion’s aura keeps at despawn, like character db pet_aura. I dont now which spell i must use, or how i must implement it.

Nothing more, thank you for your time and help. Bye

You should explore the DB a bit more, surely you’ll find what you need. Otherwise, check out TrinityCore source->SRC->Game->Spells

You can take a look at if you want some ideas on how to implement it.