iCloud: Make a sender a VIP in iCloud Mail
You can use Mail on iCloud.com to keep track of messages you receive from especially important people by making them VIPs. Your VIPs are identified by a star next to their names in messages you receive from them. iCloud Mail adds a folder for each VIP, so it’s easy to get to their messages.
In the message list, select a message from the sender you want to make a VIP.
Click the sender’s name or email address in the message header, then select VIP.
iCloud Mail adds a folder for the VIP in the sidebar.
You can also make a sender a VIP by dragging a message from the sender to the VIP folder in the sidebar.
Your VIPs are available in the Mail app on iOS 6 or later and the Mail app on OS X 10.8 or later.