I thought the brindle colouration was interesting and unexpected.In that sense they reminded me of my own accidental crossbreeds (who would not have existed had Alizin been around 11 ½ years ago!) Golden Retriever father and Malinois mother (Fawn with black mask.) 5 black pups, 4 Brindles. Both that stayed with me are brindle.
What I didn't like about the article was the fact the dog owners simply assumed a small dog would not be able to mate a large one. Of course they can! But at least yes, it was an accident and the owners are quoted as saying the dog is being neutered now.