Originally Posted by Longblades
It's disturbing that you can't tell, at 4 months of age, the difference between a Mastiff and a Malinois. It's disturbing that a so-called "breeder" would sell a pup of either breed to an inexperienced owner as both have challenges in their training, mainly to work with their built in desire to protect, but also with the Malinois a very, very, very energetic and high drive dog.
Is he a mix at all? - the only reason I ask, is because same as Longblades, not sure how you could't have known he was not a mastiff?
My brother's mastiff was very well behaved and trained, yet she still had to go to go a trainer for a while . Maybe it would be a good idea to take your fur-kid to some training.