We have certainly seen that in the five very individual Labs that we have owned over the years. Each one has its likes, dislikes, quirks, and endearing qualities. You only need to observe Dylan and Dee Dee at the dog park to see they each have their own very distinct personalities.
Dylan is our friend and lover boy. He likes making friends and playing with other dogs. Dylan will often pick a special friend to play and tussle with, or they just lick each other faces.
He's happy in a crowd and can be found running with a pack of friends. He can best be described as a social butterfly.
Dee Dee, on the other hand, is typically off on her own sniffing and exploring. She's far more likely to approach people than dogs, looking for praise, a pet, and maybe even a treat.
She even tries to coax admirers into the park just so they can provide her the adoration she deserves. Dee Dee might be described as a loner, at least when it comes to other dogs. Mom suspects she believes she's actually a people and above the dog nonsense.
So to answer your question. No, Tucker didn't replace Duke and Dylan didn't replace Tucker and Dee Dee didn't replace Dyna. And lord knows, no one could replace Dee Dee! Each one is special in their own very unique way. And that is why we keep loving the "next one."
