Indiana Code Title 29. Probate § 29-1-1-6

Sec. 6. When any judge or his spouse shall be related within the third degree of consanguinity, according to the civil law, to any of the parties or their attorneys, shall have drawn the will of the decedent, or shall be interested or have been counsel in any probate proceeding or any matter therein, the same shall be grounds for disqualifying such judge from acting in a controverted matter with respect to which his disqualification exists.  When grounds for disqualification exist, the judge may refuse to act as judge therein;  or, upon filing of a petition to disqualify such judge, stating the grounds therefor, by any person interested in the particular matter with respect to which his disqualification exists, the judge must not act therein.  The grounds for disqualification stated herein are enumerated as additional grounds, and not in limitation of applicable grounds for disqualification provided by statute or by Supreme Court rule with respect to trial judges generally.