...but the lioness still killed mommy.
Not sure why people are amazed by this behavior. Animals are wild. Eventually the lioness probably would've killed the baby. Chasing off the male lion could be just protecting her snack for later on. I've seen a house cat licking a mouse it was playing with like grooming it but then later that mouse would end up dead and not eaten.
Yup, they're just projecting human intentions onto animals. That's the biggest problem with organizations like PETA: they believe animals have human needs and desires.