In addition to what Timothy has suggested, one reason the lawyer might have taken so long is that letters are written to the heirs and public notices are placed in
newspaper to contact them.
The law gives a certain period time for these notices to be responded to.
In general, the closest relatives of the deceased are given the first priority, A spouse or children are usually first. If no surviving children or spouse, the estate will pass to the deceased's parents, and then to their siblings.
Has an Heirship application been filed with the court? If there are unknown heirs, the court may post notices in newspapers or at the courthouse as I mentioned earlier.