Redd a little problem

Redd has been a rather bad tempered boy. He bit Tom when Tom ruffled his ears, first he snarled and when Tom touched him again he bite. We now realize that he has an ear infection but still it should not have been enough to bite. Considering how he has behaved with others in the past we should not be surprised.
His training is ongoing. We will not give up in him. Redd has never growled at me nor attempted to bite me yet he has growled at Tom on a few occasions.
Strangely he seems to obey me more than Tom.
We have had two German Shep's in the past darling Jerry Lee and a soppy girl called Cassie who adored Tom whereas me she tolerated. I was the one that opened her cans of food so she tolerated me.
Cassie was the biggest dog we had, she was a huge German Shep, short haired unlike the boys both of whom are/where long haired. She was a good protector, Jerry lee would run if you said boo to him, such a sweetie he was. Now Redd is guard dog material and he is the smallest of the three. I think he should have been a police dog with his temperament. But they probably would overlook him because of his small size.
Before I met Tom he had had a white German Shep called Major, evidently a strong willed dog but obedient.
So Tom has a bit of experiance with GSD but Redd is proving a handful. He is a bit strange at times, he has attacked lampposts and then tries to bite them. He bites piece out of trees and he is obcessed with rocks which he picks up of the beach and brings homes. He want let you take them out of his mouth. I let him have them. Tom tried and Redd growled at him, with me he just pulls away or moves his head so I can not touch it. Redd must like me more than Tom is all I can think.
We have been watching the Dog Whisperer to get a few tips on handling Redd. Plus I have looked on the internet. There is no dog behavoralist nearby to get help from.
We haven't had him for that long so maybe time will tell and when he has settled in he will improve his behaviour.
Too early to give up on him yet.