When reviewing the profile of a player or parent, sometimes you will see this message "You Are Not Authorized To See Some Or All Of The Family Members" under Family Members.
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This is because the family members you are unable to see were added into LeagueOne's database via other organizations. Since you are not authorized to see other organizations' data then you are not able to see them. Once after the player is registered to your club or the parent logs into your club, you are authorized to see.