God grants life and He alone has the right to take life. Children are gifts from Him. As parents we love them and bond with them deeply, but sometimes He calls them back to Himself while they are still small and we have to let them go. Life is precious and very fragile. Don't take it for granted.
We all have questions about Heaven... Is it real? Where is it? What will it be like? God reveals hints of it in Scripture, but He doesn't tell us more because we would not be able to comprehend it. When believers die, they will immediately step from this life into eternal life in heaven with Jesus.
Because of Jesus and the sacrifice He made for all people on the cross all who believe and have faith in Him are holy in God's eyes. Only Jesus can make us fit for heaven. Come to Him with a repentant heart. You will find peace and rest for your soul.