The executor is required to administer the estate...to account for the assets, to pay valid debts and then distribute the estate either as directed by the will or as directed by law.
If the executor takes a portion of the estate for personal reasons, they can be held liable for this.
If your brothers share of the estate was $200000, then he has his share and should make sure the rest is distributed.
If his share would have been less, then he will be liable to the other beneficiaries
It seems odd this would continue after 10 years. Typically it takes months not years to settle an estate. If he is not doing the job properly, you may need to retain a lawyer and take legal action to make sure he does
To answer the question...not, its not ok for you simply because he is doing this...as a co-executor, you should take steps to make sure that the estate is distributed according to the law. If that requires involving the courts, you may need to do so
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