Interesting about the tax thing. There must be a piece we don't know, and it's not my business to inquire. There may be an exception related to dad's govt job.
My HOR was GA, the state from which I entered active duty. My state of residence, a different thing than HOR and quite often not the same, where I paid taxes and voted, I changed to FL, once I had a tour of duty there. Typical of military, if you have a chance to establish state of residency where there is no state income tax or military serving out of state are not taxed. DH's HOR was PA, and he also retained PA for state of residence, since he did not have to pay state income tax when serving out of state. I voted absentee as a FL resident the remainder of my active duty career, and was a military non-resident everywhere else I was stationed. My HOR was GA my entire career.
My military non-resident state of MD became my new residency state for tax purposes, 180 days after I left active duty. Going forward, I owed tax on both civilian salary and military retired pay. MD does allow a certain amount of military retirement pay to be exempted. Some states, such as PA, HI and others (IL could be one), do not tax military retired pay at all. The good ol' days were gone! I turned in my FL voter card and got a MD one, ditto driver's license and auto registration.
I would venture to say all states have a period of time after which people who live there automatically become a state resident, subject to all state requirements.
It's up to the OP and his family to figure out their residency and which MOC they fall under.