I believe his wife was Mary Jane Gilmore.
You can find him with his last name spelled "Lunker" on the 1870 census for Rutland twnshp., Montgomery county, Kansas. Check the family listed BEFORE his! It is the Charles Ingalls' family! Also... His father-in-law and mother-in-law's family is right after his. http://search.ancestry.com/cgi-bin/sse.dll?db=1870usfedcen&a...
He was murdered by the "Bloody Benders" most likely in Decemeber 1872 (that is when he disappeared). His wagon was found in March 1873, which prompted Dr. William H. York (who had sold him the wagon) to look for him. Dr. York was also murdered while searching for him. He is supposed to be buried somewhere near Independence with his little daughter. (also killed by the benders with her father) I have not been able to find either his grave, nor the name of the little eighteen-month-old girl.
It appears that he had also had a son who died in May 1870 from pneumonia. His name was Robert. He is listed in the mortality scheduals. In one schedule his last name is given as "Lunker" and the other as "Lanker".http://search.ancestry.com/cgi-bin/sse.dll?db=mortalitycen&a...http://search.ancestry.com/cgi-bin/sse.dll?db=usmortality&am...
I have not located his or Mary's graves either. I am starting to fear that they have "prairie graves", perhaps on their farm.
I know that after the murders were discovered his and his daughter's bodies were identified by his father-in-law. He had left to take his daughter back to Iowa to live with his parents after his son and wife's deaths, when he stopped at the Bender farm. 1872 was one of the coldest years on record, and according to news reports there was 6 inches of snow. It is no wonder that he stopped at their little Inn. He and his baby must have been almost frozen.
I have been researching the Benders and their victims, and have to say that the tragedy of this particular family has really touched my heart. To have lost your son, and then your wife is tragic enough, but then you see the end of the story and well.... I hope this has been helpful. If you have any other information I would appreciate it. Thanks.