During estate planning there may be extra documentation that is needed to make sure that all wishes are provided for, these are called ancillary documents and include medical affidavits, guardianship documents if there are children involved and a power of attorney. Ancillary documents are simply a part of the whole package that is prepared during estate planning. Ancillary documents are important in planning an estate and insuring that each document is sound and unable to be contested is part of an estate planner's duties. These planners can recommend the necessary ancillary documents for individual situations. Each estate is different and each will require a different set of documents. Ancillary documents should be kept with the last will and testament and copies provided according to the estate planner's guides.