All petz (even hexies) have the personality of one of the original breedz.  Hexed breedz may have their own customized voice.  Offspring inherit the voice/personality of one parent.  They do not have a mixed personality.  The personality can be inherited completely independently of shape or color.  A cat pet can look exactly like one parent but act and sound like the other.

I have noticed, however, a tendency for personality to match ear type, especially after several generations.  Most selective breedz will have ears that match the voice/personality.

Petz 5 has a pretty common glitch causing mute petz.  If the petz is descended from an original breed, and that is the voice it is supposed to have, you can use the unmute utility from Odd-Petz to fix it.

Original Catz 3/4 Breedz
Alley Cat
Hisses when photographed.  Generally gets upset at any little thing.  Original version is always sick and has fleas.
B+W Shorthair
Likes to hunt and stalk things.  Often has angry eyelids.  Looks angry when posing for the camera.
Happy and playful.  When posing and in other stances, they usually drop one eyelid and have the other one raised.
Chinchilla Persian
Very soft voice and airy purr.  Spends a lot of time sitting still and blinking.  Usually falls asleep when picked up.  Poses for the camera with eyes at a slight angle.
Maine Coon
Jovial and playful.  Likes to prance around.  Poses for the camera with eyes wide open.
Orange Shorthair
Terrified of almost everything.  Gets frightened if photographed and runs around in terror or poses like shown at left.  Usually has a worried expression.
Chinchilla Persian
Low voice.  Fond of licking and rubbing against the hand.  Often falls asleep when picked up.
Russian Blue
Even tempered and not overly playful.  Quite often strikes a pose like this one when photographed.  Eyelids usually even and straight across.
Always the show off.  Lays like this or sits with eyes closed often.  May also stretch when photographed.
The clown of the group.  Does funny little tricks often.  When photographed, sometimes poses with eyes wide open.
Added Catz 5 Breedz
Desert Lynx
Seems very similar to Russian Blue.
Egyptian Mau
Seems very similar to Russian Blue.
Honey Bear
Seems very similar to Maine Coon.
Japanese Bobtail
Acts similar to a Siamese but behaves differently for the camera, sometimes posing with angry eyes.
Scottish Fold
Acts similar to a Tabby.
Original Dogz 3/4 Breedz
Feet are turned inward when walking.  Generally a tough-acting guy.
"Yappy."  Likes to drag his butt on the ground.
"Yappy" like the chihuahua, but more of a show-off.  Likes to do headstands and other tricks.
An intelligent and friendly dog.  Often poses very show-like for the camera.
Great Dane
Friendly but rather clumsy.  Has a tendency toward tripping over his own feet.
Loyal and good at tricks, but often afraid of the camera and heights.
Very playful.  Always doing silly tricks and growling at things.  Squeaky voice.  Often holds eyelids unevenly.
The only breed that acts significantly differently.  Struts around facing upward.  When photographed usually lies down like shown here.
Playful and likes to scratch and dig.
Shakes a lot and also falls asleep when picked up.  Not a very active breed.
Added Dogz 5 Breedz
German Shepherd
Golden Retriever
Similar to the Labrador.
Jack Russell
Similar to the Chihuahua.
Similar to the Bulldog.