Feral Children are those who were raised in the wild with no or negligible human contact. Isolation from Human society causes them to loose communication and language skills as well as social conduct.

Feral children who cross a certain age, say, 6 years may permanently loose their adoptation skills to learn a language and communicate properly.

Perhaps Rudyard Kipling's MOGLI is the most famous frictional Feral Child and the inspiration behind another frictional hero, Tarzan, but India is really a home to a number of rare feral children.

One such feral child pair were Kamala and Amala who were raised by a she-wolf.
Theirs' is a heart-rendering story that won't fail to move you.
Read it here