My Shetland Sheepdogs are quite at ease with the lambs, but Perkins, the Australian Cattle Dog, can't be in with them, he does give them a nip. Jarrah on the other hand has gone clucky on sighting them and has made milk.
She wants to adopt all 3. I've had this happen before, the ACD's can be excellent mothers and some are prone to phantom pregnancies and this urge to adopt babies of any description. My foundation female wanted to adopt baby chickens for instance.