Thank you for sharing your dream and the question. Excellent question and beautiful dream!!!
I don’t think your grandmother is your literal grandmother (could be) but sense that it could represent your inheritance from the Holy Spirit. Check out Isaiah 11:2, count, and that might answer your question :). Perhaps, the gift of knowledge or spirit of knowledge(as per Isaiah 11:2) is what has been activated in your life (and encouragement to use it) but the rest are still available to you. The Bible has various mentions of spiritual gifts and the numbers vary and the type may differ slightly in the accounts. I encourage you to research your Bible about the different instances (Corinthians, Romans arare good books to start but there are other mentions) that spiritual gifts are mentioned for your knowledge.