When discussing the reliability of memories, the memory of a is considered to be the most vulnerable to suggestion, and therefore, perhaps the least reliable?

The answer is "the memory of a preschool-aged child".

Preschoolers start to recall particular occasions from their past - that is, "I remember the day I wore my green bathing suit to the shoreline and met my cousins there," as opposed to, "I recall the shoreline" - when they can build an account about what happened. The working up of personal memory begins here. 
As preschoolers, they begin recalling dynamic ideas, for example, colors, how to tally to ten, and the ABC's. They store this data in their transient memory, and afterward battle to recover it when they have to. Sooner or later, however, the recovery procedure ends up quick and the struggle vanishes. They don't recall shading names - they just consequently know them.