Here's a pic of me and lovely Isis, my Shepherd rescue. She is, without a doubt, the most wonderful dog of all time.
This pic was taken during a hike that is done with a German Shepherd club and a professional dog trainer who is a K9 officer and marine.
The purpose of the hikes is to socialize the dogs, get them used to being around people and children and such. Very effective. My dog was afraid of people and dogs, now she is doing much better even allowing herself to be mobbed by children without cowering.
Shepherds are interesting. They have a number of personality traits that can manifest themselves and are usually quite pronounced.
Most of these traits are not serious, such as one who becomes very upset when the other dog that she lives with leaves her general vicinity, she just starts crying like it's the end of the world.
Most of the dogs are just fine around children, as there are a number of special needs children that come on these hikes. Many of the dogs are off leash the whole time and no problems.
There is at least one shepherd though who has to be muzzled the whole time and is not a dog I would want around kids. Beautiful dog, a lot of nervous energy, would make an outstanding police dog.
It's incredible to see the calming effect on this dog that the K9 officer has over it. Dog just turns to putty in his arms. The guy is a dog magic man.
But my point in all of this rambling is that with shepherds, the aspects of their personality are usually easily visible very early on such that one can tell of the dog has a suitable temperament to be around children, and there are definitely some shepherds who should not be around children.