Appropriate preposition to go with “concerned”

Question

He is deeply concerned for vulnerable children.

Is this correct? Or is there a better preposition to use instead of for? What exactly does this phrase mean?

What about "He is deeply concerned with vulnerable children"?

Answer 1

There is a few variation to be used with to be concerned.

One can be concerned with something. This would have a meaning similar of to deal with

I am concerned with daily maintenance of our machines.

One can be concerned about something/someone. This would be the preposition which could be use in your case, but it would give it a meaning of caring about.

He is deeply concerned about vulnerable children

Of course, for seems to be used, although I rarely heard it (which is in no way an indication of the frequency it could be found), it is used.

EDIT: See Dan Ray's answer for a use with the for preposition.

Answer 2

To have a concern for something means there is something your attention is on, something you're committed to. I have a concern for my boss's satisfaction with my performance, the amount of time I spend on Stack Exchange sites notwithstanding.