I am sorry for your loss. I would hire counsel and demand return of personal items as well as damages for items that were destroyed. Depending on the response and the amount of loss you could file a civil complaint. Finally, if you have insurance, you submit a claim.
There is liability insurance for almost everything! If you can be sued and if you have assets to protect, I definitely recommend coverage. A good insurance agent will provide you with several options for plans and coverage. Good luck!
Your best bet would be to call the probate clerk and see if you can do this. The problem is that the small estate transfer affidavit specifically states that no application for probate was filed, so I am not sure, even if you are able to withdraw the petition, you would still be able to use the small estate procedure. In addition, the filing fees are the same, so you would want to try to avoid paying a duplicate filing fee. You might also ask the probate clerk if there is a process to...
The mother is required to give father written notice of intent to relocate at least 60 days prior to moving. The father then has 30 days to contest relocation by filing a Petition, either to prevent relocation or to modify legal decision making and parenting time. Even if the mother fails to give written notice, father should file his Petition as soon as possible.
This sounds like the highest form of fraud and is also criminal. I would contact the D.A. before doing anything else. It's hard to believe there's not an honest attorney and honest judge out there. I have also added fraud to your practice area.
First make sure you have the proper insurance. Then decide if you are willing to let the relatives stay in the house as tenants. If yes, enter into a lease agreement that requires them to insure against liability and property damage and if no, give them notice to vacate. I highly recommend using a residential landlord tenant attorney to handle this.
You will either need an Order from the Probate Court specifically authorizing your removal of your brother from the property, or you will need to serve him with a Notice to Vacate and then proceed with eviction. Make sure you are working with a probate attorney for the first method or a residential landlord-tenant attorney for the second. In other words, don't do this on your own.