cooper's sister

My family, sans me, went to the animal resort/farm place yesterday it seems and who should they meet? Cooper's sister. I think it might be his little sister but I'm really not sure. She's a lot smaller than Cooper who is growing at such an alarming rate its scary. He's matching Mango already, who, I give you, is a rather small Retriever but still, she's a full grown dog and he's barely into his fifth month. He's now known affectionately as Mickey Mouse cos his ears are too huge for his face. It's a phase all German Sheps go through I'm told. He's such a cutie.