How can I force my brother to help financially for our aging mother?

Are you 68 or is your mother 68 years old?

Your brother has no obligation to financially provide for your aging mother. And neither do you. You do not have to have her living in your house, either.

If mom is in California I assume she didn't pay her state taxes either. Under your other post I commented about federal taxes. Apply for MediCal for medical coverage if she has low income. The state will probably pay her very high Medicare Part A premium because it saves the state Medicaid (MediCal) costs in the long run because Medicare picks up costs first.
Much as I hate to advise this to someone who basically skated on her tax responsibility for 30 years, your mother may be eligible for Supplemental Security Income due to her age and apparent lack of income. That safety net resource is applied for through the Social Security Administration 1 800 772 1213. She will possibly also qualify for SNAP (Food Stamps, AKA CalFresh).
Give up on help from your brother.
Just wondering why nobody got mom out of that employment/tax situation years ago so she would have a better life then and now.

Another post by the OP:


https://www.agingcare.com/questions/what-can-i-do-if-my-mothers-30-year-long-employer-didnt-allow-mom-to-do-her-taxes-470596.htm?orderby=recent

It seems mom hasn't paid taxes on income?

Why is this his responsibility in your eyes?

JoRogen, according to your profile, it reads your Mom is 68 years, that's pretty young in today's world. Call your local Agency on Aging to see what type of help she can get. Since she can't get Medicare, each State has Medicaid that can help out for her health care.

Not to be nosy, did your Dad or your Mom's husband work getting payroll checks? You may want to check with Social Security to see if your Mom can get match funds. She would need to qualify, such as having been married for ten years.

Not his responsibility.

IF you live in a filial responsibilty state in the US, or in a country that mandates that chikdren financially support their indigent parents, your mom might be able tobtake your brother to court.

Otherwise, adults are supposed to pay their own way.

Why is it that your mom can't afford her care from her own resources or from Medicaid?

You can't.

Neither he nor you are responsible for helping your parents financially or in any other way.