I believe you may be referring to Sarah and Abraham in Genesis 18:10-15 "then the Lord said, I will surely return to you about this time next year, and Sarah your wife will have a son"
I know she laughed, however, Abraham was concerned when the Lord questioned her laughter. gulp!
I'm sure GOD expected them both to be in shock mode, but Sarah did deny laughing - also expected because she must of been scared when GOD quesiton her lol. I think GOD probably laughed in the background as well when He told them this