Make an inference about the “faint, muffled sobbings and slubberings.” What do they mean?

The sounds were the noises made by Kiche's newborn cubs.

Faint, strange sounds came from within. They were sounds not made by his mate, and yet they were remotely familiar. He bellied cautiously inside and was met by a warning snarl from the she-wolf. This he received without perturbation, though he obeyed it by keeping his distance; but he remained interested in the other sounds—faint, muffled sobbings and slubberings.

Nevertheless, he made out, sheltering between her legs against the length of her body, five strange little bundles of life, very feeble, very helpless, making tiny whimpering noises, with eyes that did not open to the light.