"Something you forgot to tell me the first time around."
You've been so involved with your case guess, after a while they just forgot to tell you.
Don't forget to tell me of anything, no matter how small, that comes up.
I forgot to tell you before, but I'm thinking of getting married again myself.
I forgot to tell you the most important thing in my last message!
I forgot to tell you that his name came up long before the phone call.
How could a grown woman forget to tell a man she had been married before.
"He probably went off on some business deal and forgot to tell you."
And perhaps we should forget to tell anyone else about it.
"Did you hold a press conference and forget to tell me about it?"