Who will be in heaven?
While there may be others we don't know of who God has created or will create in the future, we know the following will be in heaven: God himself (Deut. 26:15; Matt. 6:9); all God's people—covered by Christ's blood—from earth who have died (Rev. 4-5; Luke 16:22, 25; Heb. 12:23); righteous angels (Luke 2:15; Matt. 28:2; Heb. 12:22).
For more information on this subject, see Randy Alcorn's book Heaven.