Kids aren't interested in how much you have, or where you came from. They won't necessarily be "grateful" in what you provide for them, because they don't quite get that "being provided for" isn't supposed to be the norm. They show their gratitude by growing and thriving, and eventually when they grow up, they'll finally "get it" and know. Love them, provide for them, survive their moments of immaturity, console them when they need it, guide them even when they don't want it, and they'll be come a reflection of what you want the world to be.

It's the foster kids who become permanently adopted who are a little bit different. They're the ones who understand that love isn't to be taken for granted, and so they appreciate it when you become the parent who will always be there for them, in ways that people who have never been so alone will ever fully understand.