The Diving Bell Calf is the offspring of a Bull and Diving Bell Cow. When you harvest milk from your Dairy Farm (with 1 Bull and at least 1 Diving Bell Cow inside) there is a chance that a Diving Bell Calf will be born. When you harvest from your Cow Pasture with at least 1 Diving Bell Cow there is a chance that a Diving Bell Calf will be born.