:-) 'Big' is relative
Our 10 month old (yesterday) Labrador Retriever (Yellow Lab) 'Puppy' weighs 65# (at least and is all muscle) and is approx 5' long when she stretches out. And standing on her hind legs she can reach anything that's 1/2 way on our 36" high kitchen counter.
And she's till growing. Now when she sits she can look out the living room window. Until recently she had to stand on her hind legs. It's a good thing our daughter picked a female pup, her brothers are prolly HUGH now.
(and we thought ours was the runt of the litter)
And still growing...goodness.
I've been looking at pictures of full grown GP's. They will be huge. I'm glad they're both females, they won't be as large or heavy as males.