A guard is static, but can be very useful. When guarding something, the person stands at attention and blocks all comers.
A guide moves with you. He or she may not spell out all of the details worth noticing, but they'll call attention to what's worth your time and help you chart a course.
In parenting, in leading, in working, and in living, we need to decide when we must guard and when we must guide.
We also have to decide when we need which in our own lives.
A big mistake is to assume everything needs to be guarded. When in doubt, err on the side of guidance. That's where the mutual journey is.