You cannot bring a contest in an estate simply because you don't like what is happening. You must have legal grounds. You must have been wronged in some way and you must have a legal remedy.

You must have some right to an inheritance based on:
your relationship to the decedent
the wrongful death of the decedent
promises made by the decedent
performance on your part which benefited the decedent
some defect in the testamentary document signed by the decedent
some wrong action by another person that could cheat you out of your inheritance

You cannot contest a will simply because you don't like the provisions, or because you received less than you felt you should have received, or because the provisions were, in your opinion, unfair. You must have legal grounds, which, if supported by the evidence, would cause the Will to be rejected by the Probate Court.

Briefly, legal grounds for an estate contest include:
Lack of testamentary capacity - the testator was insane or incompetent at the time the Will was signed.
Improper execution - there were not enough witnesses, or for some other reason the Will was not properly signed.
Undue influence - someone took advantage of the testator's susceptibility and caused him to make out a Will different from what he would have made on his own.
Fraud or mistake - the testator was induced to sign the Will as a result of fraud, deceit, or a mistake.
Revocation - the Will was canceled or revoked by the testator.
Bogus Will - the Will offered for probate was not the Will of the decedent. (This might include forgery, for instance.)

Excerpted from The Complete Book of Wills & Estates by
Alexander A. Bove, Jr., Esq. New York:
Henry Holt and Company, 1989.

Briefly, legal grounds for wrongful death action include:

 

A relative has been killed by the wrongful act of another person.
The other person has financial & is insured.