Hereditary Empathy is the anomalistic ability to genetically alter oneself to take on any minor physical, emotional, or mental trait shown by any of one's (direct) ancestors, including known anomalistic abilities. This ability is seemingly a culmination of many genetic mutations in the ancestry of the individual, providing a sort of sampling of their ancestors' powers.
A severe limitation of this ability is that one would need to know for certain that the trait, characteristic, or ability they wish to emulate is present in their ancestors or have experienced it (as with a parent or other living relative). Thus, only by knowing an ancestor had a specific power is one able to access the ability within themselves. Otherwise, it lies dormant and unused. Likewise, while most Evos have secondary abilities and others may possess multiple abilities, a descendant with Hereditary Empathy is only able to access the primary powers of their ancestors. If the primary power was one that "farmed" other powers, the main ability that would be acquired would be the one that captured or copied other powers. This would, therefore, be unusable and lay dormant because the descendant would lack the proper genetic code to utilize a second "power farming" ability.
It is also much more difficult to emulate characteristics the closer the relative, though the cause for this is unknown. While it is not possible to shape-shift, some minor alteration of appearance is possible (such as hair color, eyes, skin tone, etc.). This does NOT extend to changes in sex, height, weight, hair growth, etc. for logical reasons. These physical characteristics could be known by simple photographs, but only by some documentation or stories passed down from generation to generation would one possibly know of superhuman abilities.
It is very likely the person with this ability would be either confused by it or oblivious to it.