The Bible tells us that angels are spiritual beings - that is, they don't have physical bodies like you and I do. The Bible calls them "ministering spirits sent to serve those who will inherit salvation" (Hebrews 1:14).
But at times they are able to take on physical bodies, or appear to us in physical form. Admittedly, this is hard for us to understand - but the angels are God's servants, and He enables them to take on physical bodies if it becomes necessary. The angels who appeared to the shepherds to announce Jesus' birth filled the heavens with their presence (see Luke 2:13-14). When the women came to Jesus' tomb on that first Easter morning an angel met them to announce His resurrection, and the Bible says, "His appearance was like lightning, and his clothes were white as snow" (Matthew 28:3).
The Bible indicates, however, that most of the time the angels are invisible to us, and we are unaware of their presence. But that doesn't mean they don't exist! God loves us, and one of the ways He safeguards us is by His holy angels.
Thank God for His love for you and your son - and the most important thing you can do is tell him about God's love for him. The angels are an expression of that truth. But even greater is what God did for us by sending His Son, Jesus Christ, into the world for our salvation. Is He at the center of your life?