I need to have an estate property that is still in probate partitioned.

You cannot bring a partition action if your share is derived from an estate and you have no present title.  First, you must compel distribution of your title, then bring a partition.

Unfortunately you are correct- partition is the way to go. In a partition action, the court literally splits the property in half and gives half to each owner by ordering a judicial sale. In the course of the action, if the parties can agree to enter into a stipulation of settlement to sell the property on the open market and split the proceeds, that will result in much more money to each owner. Otherwise, the legal fees and court costs of a partition action can eat up all the equity in the property. However, it is usually necessary to commence the partition action first in order to get the other party to settle. There is no defense to the action- one owner cannot prevent the partition from being ordered if the parties cannot otherwise agree to a buyout of one party by the other or some other arrangement.