What should i get engraved on a ring im buying for my boyfriend?

We've been together for about 5yrs or so. We have 2 kids... And im getting him a welcome home gift. [hes at florida] so im thinking a ring and i want it engraved. But idk what i should have put on it. Im skippin the aniversary thing just in case. Cuz u never know if that will change. So what can i put on his ring that would be special. But wont change if we were to get maried or brake up?