Raised hair while playing
We have a 4 month old GSD male and he is now playing a lot more rough. He is not neutered male. I am concerned he is becoming more aggressive as he gets closer to sexual maturity. At the dog park this morning his hair became raised at other dogs and his bark became more deep. Any suggestions on how to control his more agressive behavior as he gets old and reaches sexual maturity. I don't want him aggressive in public or charging other dogs in public becasue he is not neutered. He is going to be about 90-97lbs and i just want him safe and presentable in a public setting.