Aggressive 4 1/2 year old male Bulldog

Question
My 4 1/2 year old male English Bulldog has become suddenly VERY aggressive with all house members.  He is fine with strangers, etc...but has now bitten my 11 year old, and snarls at my 10 year old and me!  Vet says physically that he is healthy.  Is he getting old? Thinking he is the Alpha? What can I do??  I cannot afford a trainer, I wish that I could.

Answer
I hear this story quite often and the cause can be a variety of things.

Yes, the dog is getting older. If he's not neutered, it's still not too late. If he was going to exhibit alpha dog behavior, it would probably have shown itself before now. Perhaps his eye sight isn't what it used to be or his hearing. Both of these could cause him to react differently to people.

Try to determine what is going on when this occurs. Is it over attention or food or a toy or is it territorial, possessive behavior over a certain person or "his" area in the house?  Once you figure out what triggers it, you can adjust accordingly. If the dog is crate trained, put him in his crate for a "time out" when this occurs.

I honestly don't think training is going to do you any good at this point.  You've had the dog his whole life I assume and you know him better than anyone.