Accidentally posted this in the wrong section.

My father is a SGT 96B20 assigned to a fenced unit at Fort Lewis, WA.
His mother (My grandmother, obviously) is 90 years old, and in very poor health at this time. Since he is an only child, and the only living relative that can take care of her now, would that qualify him for a compassionate reassignment?
Redstone Arsenal is less than 10 miles from where she currently lives, and since the first part of EOD school is there, he figures that it would make sense for them to need a 96B to work in an S2, at least for processing clearances.

There's a lot of information about this topic and many more what if's. Compassionate action are based on two categories: (1) Temporary (resolvable within a year) and (2) Not expected to be resolved within a year.

Below is some temporary criterium:

AR 614-200, Chapter 5, Section III, Compassionate Actions
5–17. Compassionate requests when problems are temporary
The following criteria is in addition to the criteria listed in paragraphs 5–14 and 5–15.
a. The problem must be temporary and resolvable within 1 year.
b. The problem neither existed nor was foreseen at the time of the latest entry on active duty. Reenlistment without a break in service is not considered to be the latest entry on active duty.
c. Commanders with GCMCA, on a one–time basis, may—
(1) Temporarily defer, up to 60 days, Soldiers’ AIs when the request for family travel was submitted late due to extensive evaluation and testing of family members identified during mandatory medical screening in support of the Exceptional Family Member Program (EFMP) (not applicable to IET students).
(2) Delete Soldiers’ AIs when, within nine months of Soldiers’ report date—
(a) The spouse or minor child is deceased.
(b) There has been a documented rape of spouse or minor child, and the Soldier’s presence is essential to resolve related problems.
d. Situations not stated in c, above, will be decided by HRC (AHRC–EPO–A). The following are examples of conditions that normally warrant approval:
(1) Terminal illness with less than 12 months’ life expectancy of an immediate family member documented by attending physician.
(2) Scheduled major surgery of Soldier’s spouse or minor child with 12 months or less recovery/rehabilitation documented by attending physician.
(3) A recent severe psychotic episode involving a spouse or child.
(4) Soldiers’ minor children are being made wards of the court or placed in an orphanage or foster home as a result of family separation. Separation must be the result of military service and not of neglect or misconduct on the part of the Soldier.
(5) Adoption cases in which the home study (deciding if a child is to be placed) has been completed and a child is scheduled to be placed in Soldiers’ home within 90 days. Additionally, if Soldiers are pending reassignment action, the Soldiers must have initiated the adoption proceedings before notification of reassignment.
(6) Soldiers en route from an accompanied OCONUS tour to an unaccompanied OCONUS tour may be deferred for up to 30 days. The deferment is for settlement of family when the Soldier’s presence is required for unforeseen problems.

Thank you for the information!
So how would he go about getting the ball rolling with this?
His supervisor has no clue whatsoever. Who would he contact first?

Gather up all supporting documentation and include it with your DA Form 3739. Take it to the commander for determination.

You can go see AR 614-200, page 41 for an example on how to fill out the DA Form 3739.

Supporting documentation
The following documentation will be included (as appropriate) with DA Form 3739. (See fig 5–2.)
a. Medical problems. A signed statement from the attending physician giving the specific medical diagnosis and prognosis of illness. The statement will include date of onset, past and anticipated periods of hospitalization, period of convalescence, and anticipated life expectancy for terminal cases. The statement will list any other factors that establish the Soldier’s presence as having a bearing on the medical condition. For cases involving reassignment from OCONUS location where medical care for family members is not available, include documentation from appropriate medical authorities stating that fact. (See para 5-15g).
b. Legal problems. A signed statement from a licensed attorney stating the problem and the reasons why solutions other than reassignment of the Soldier are unacceptable. If applicable, a copy of court order, divorce decree, or other pertinent legal documents will be submitted.
c. Rape/child abuse. Statements from police, social service agencies, and/or examining physicians.
d. Marital and dependent status. When cases involve reassignment of Soldiers to dependent–restricted tours, a statement by the Soldier, witnessed by an officer, will be included. It will specify that the Soldier has been advised that travel for dependents at Government expense is not authorized. (See JFTR para U5222D.)
e. Other problems. Supporting statements from responsible persons (for example, clergymen, social workers, court clerks, American Red Cross personnel) who have personal knowledge of the problem.

Thank You!!!!!

You're welcome. That's why we are here.

I hope everything works out with your dad and grandmother.