Wow I can't believe my original question got deleted but anyway.
A few things going on here, so my Grandpa bought a lost iPhone 4 (New Condition) for 40 dollars off some guy. So technically the iPhone 4 is still lost because the owner didn't sell him it, some random guy did. So he brought it home, and I unlocked it seeing that his facebook was still logged in. I could post a status on his FB asking who's phone this is and how I can contact him. So i don't know what to do because I know its haram to steal, so I wanna give it back. But my mom won't let me because my grandpa already paid and he wants to send it to his relatives in a foreign country.
To understand this, think of it like this. An iPhone 4 for free to our family is like the biggest diamond in the world.
So what do I do, even if my mom doesn't want me to return it?