You have sent a notice for partition and they have replied with baseless allegations, some of which has hurt your sentiments, right?

For filing a defamation case u/s 499/500, some ingredients are essential:

You should have proof to prove that they were wrong allegations and was intended to spoil your reputation in the society as well as to defame your name and fame in the society;

How did it affect you and what are all the losses you have suffered (mental)

other issues as mentioned in the provision of the law referred.

You may apprise a good lawyer about the defamatory contents in the reply notice and can arrange to issue a notice to the people who offended you (not the lawyer who issued notice under his banner), wait for the reply or compliance of the demand made in the legal notice, after that you can proceed with a criminal private complaint before the jurisdictional magistrate court.

1. You can prosecute your siblings for defamation if you wish.

2. The damages can be sought on the basis of the reply received from your brothers. Before doing so you may issue a lawyer's notice to them.

3. The suit for damages will not affect the progress of your partition suit in any manner.

1) you are entitled to share in property on your father demise

2) lawyer merely issues notice based on instructions issued by client ie your bother

3) no case is maintainable against lawyer

4) you can send rejoinder through your lawyer and deny all the allegations made in the reply and call upon your brothers to withdraw all false and defamatory allegations made and tender an unconditional apology

5) proceed with filing of partition suit

No case against lawyer will stand as a notice is addressed to you as instructed by your siblings.

you can file a defamation case after sending a Notice .

To continue with the partition suit, your advocate should send a Rejoinder / reply, to the reply notice denying the allegations and warning them against a defamation charges if not tendered an apology.