I have a problem with my 5 year old male beagle. He is an amazing dog, well behaved (most of the time) and very affectionate and I love him to bits. When he was younger and new people would come over he never had a problem. As the years went on when new people came over he would bark at them and sniff them for a few minutes and then be fine. Lately is has progressed further and now he has bitten a new person that came over, this has happened twice He drew blood both times but it didn’t need stitches. We have had a professional trainer come to our house to work with him in the past when the barking at new people started to occur. I am just worried that the progression of aggressive behaviour could get worse. Any advice would be greatly appreciated.