To be in Jamaica and see a Rastafarian, hands held high, looking up at the 8 ft tall plants, praying for the Lord to bless his garden, is truly a blessed experience. Yes, Christians can smoke ganja.
Write, write and write some more! Some day your son will feel blessed you took the time and love to do this. As you write, you may want to pull out little gems (poems, picture books, chap books) from time to time as they apply to his development and understanding.
At the risk of being cliche, it's the process, not the product. Just let those creative juices flow, and see where it takes you. You don't have to know ahead of time where it's going. Just commit to creating everyday. Pretty soon you will soar.