Being called a child of God is a title that should give you a sense of how much the Father loves you. For the same God who created all the universe to call you His child is a big deal, it means that He has chosen to make you His own.
3 See how very much our Father loves us, for he calls us his children, and that is what we are! But the people who belong to this world don’t recognize that we are God’s children because they don’t know him. 2 Dear friends, we are already God’s children, but he has not yet shown us what we will be like when Christ appears. But we do know that we will be like him, for we will see him as he really is. 3 And all who have this eager expectation will keep themselves pure, just as he is pure. (1 John 3:1-3, NLT)
Though the world is unable to recognise the truth about you, take confidence in the truth of God's word. You are a child of God and when Jesus returns this truth will be manifested to all. In whatever manner Christ appears, we who are God's children will be of the same stock. When we see Christ, this will enable us to fully grasp our own identity more completely. Until then, we seek to live a pure life according to that which we do know about Christ (as revealed through the scriptures). Jesus kept Himself pure; therefore, as fellow siblings, we too must do the same.