Dreams dictionary: Sibling

Dreams dictionary: Interpretation 1
To see your sibling in your dream indicates unresolved issues with your sibling or unresolved issues from your childhood that needs to be confronted. Consider their actions in your dream and how it may be a reflection of your own self and your character.
Dreams dictionary: Interpretation 2
To see someone else's sibling(s) in you dream represents a quality or characteristic of that sibling that you need to incorporate and acknowledge within yourself.