iCloud: Make a sender a VIP in Mail on iCloud.com
You can specify certain people as VIPs to keep track of messages they send. Your VIPs have a star next to their names in the message header. iCloud Mail adds a folder for each VIP, so it’s easy to get to their messages.
In Mail on iCloud.com, 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.