A short note can be reread on days its writer never knew would be difficult.

When you write something kind, you are writing to a day you cannot see. They may read it once and put it away, then find it again in a week when everything has gone wrong. Small written things last strangely long. They can be reread, which speech cannot.

Someone you know is having a harder time than they have mentioned. Write four sentences and send them, without needing a reply or an occasion. You will not usually find out when it landed, and that is not a reason to skip it.