Fainting 
To dream that you are fainting indicates your difficulty in dealing with subconscious concerns or emotions. You need to be more open.
To dream about a family member fainting suggests that you will bear witness to some imprudent behavior from that family member.
Blackout
Experiencing a blackout in a dream suggests that you're being cut off from something which could be anything from civilization to a specific person or resource. Whatever the case, you feel that you need this contact or resource in order to be successful and you feel 'in the dark' without it/them.
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