If there is life elsewhere in the universe, then you can be sure that God created it and put it there. It didn’t happen by chance — anymore than life here happened by chance. The Bible’s opening words underline this great truth: "In the beginning God created the heavens and the earth" (Genesis 1:1). Elsewhere, the Bible assures us that Christ — God’s divine agent of creation — created everything, and "without him nothing was made that has been made" (John 1:3). Never forget: You and I (and your son) aren’t here by accident. God put us here — and He put us here for a purpose.
Because of the vast distances that are involved I suspect we’ll never know for sure if there is life elsewhere in the universe. But some day we will if we know Christ — because in heaven all the things we don’t understand right now will be revealed.
Encourage your son to explore this incredible world God has given us. But most of all, encourage him to discover the greatest truth of all — that God loves him, and Jesus Christ wants to come into his life and be his friend.