A Quadrupedal Animal Character and a Bipedal Animal Character Together is Not Always Furry Confusion
Typically, a four-legged animal character and a two-legged animal character are at different levels of anthropomorphism from each other, with the former character being "non-anthro" and the latter character being "anthro." But this is not always the case. For example, a quadrupedal animal character and a bipedal animal character of the same (or related) species on the same level as or similar level to each other is not Furry Confusion as long as the two characters are capable of walking on two legs. Also, if a two-legged animal and a non-bipedal-stance-capable four-legged animal are treated on par with each other, then there is very little or no Furry Confusion unless the two animals are of the same (or related) species.
So this settles not so much on the mere stance and that animals assume (bipedal, quadrupedal, or otherwise) as it does on how the animals are treated in the work.
- The original Babar books and TV series
An Animal Character With a Pet is Not Always Furry Confusion
An animal character who owns a pet is usually viewed as being Furry Confusion more than a human with a pet is. But, depending on the situation, this is not always the case. For example, it's technically no more Furry Confusion for a mouse or any animal beside a dog to have a pet dog than it is for a human to have a pet dog unless there are "anthro" dogs in the same universe. It's just Furry Confusion for any animal to have a member of its own species as a pet or be a species more closely related to their pet than, say, Curious George and Yellow Hat.