Well-said, Rosemary.
I know several people on the site have also expressed that they believe they shouldn't reveal when they are doing something for someone else in accordance with Matthew 6:3, because they have said that announcing a good deed in public will cause one to lose their heavenly reward.
I have to admit to wanting also wanting emoji in the past, but am now on the fence because I find myself agreeing with both points of view.
Avisanct, I don't know if this will help, but since we don't have a prayer emoji, when I read a prayer request or even just a post I find myself praying over, I tend to use the heart emoji to at least let the person know that someone read what they shared and is thinking of them.
If you are able to PM, you might want to send them a message as well.
God bless and welcome to CC.