Do these following animals have mammary glands?

Frogs don't because their offspring do not need milk, and their offspring are usually independent from birth (well, and also their amphibians. Only mammals have mammaries). Kangaroo offspring are very dependent on their mothers the first couple months or so of their lives. The joeys (the term for a kangaroo offspring, like lamb) are so literally attached to their mother's teat (the part the milk comes out of) that to try to pry them off would rip out their lips.