Suggestion for sharing to multiple email addresses

I have 3 kids with Kindle and am happily using Calibre to send them their books by using Sharing to their kindle email address.

Problem is that I never remember which child has which Kindle email address abc_1234@Kindle.com, cba_4321@Kindle.com, etc

My suggestion is to make an extra column to I can add a name to each email address and easily know who it belongs to.