Labs are similar to GSDs in that there are American labs, and there are English labs, and there are everything in between. Americans tend to super-size everything, but I think that there are lines of labs that are not as large as GSDs. For a female that may be the case here, she is out of a smaller line of lab, and she got that size. Possibly, though it isn't impossible for her growth to be stunted as well.
Mongrel is not a derogatory term. I am sorry you took it as such. My point was, when you take a breed that has a LOT of variation in it between the lines, like the GSD has, and mix it with another breed of dog, you really cannot guaranty anything with respect to bodily dimensions.
My other comments were understood as they were intended. I find it interesting when people who work at shelters buy dogs at pet stores, or let their mixed-breed dogs pro-create because most of them tend to be totally anti-breeding and understand that pet stores are fed by puppy mills. So it genuinely surprised me.
Jenna, RN CGC & Babs, CD RA CGC HIC
Heidi, RA CGC
SG3 Odessa, SchH1, Kkl1, AD
Ninja, RN CGC & Milla, RN CGC
Joy, Star Puppy, RN CGC
Dolly CGC & Bear CGC