Heather LaRue is one of the hero characters in the DLC Breakdown, known as "The Mother". Her character model is taken from the recruitable character Ashley Lake in the original State of Decay, but her description, traits, and skills are completely different.
Heather is unlocked by preparing a feast in the Cooking Area. Challenge is available from Breakdown level 2. It is recommended to not waste any food unless it is for Snacks and do *NOT* cook a big meal because all survivors in the community will then be Stuffed locking the Cook A Feast option for a while.