Passage: In 1951, with secret means of communications established, Wolters sent his first letter to Speer in five years.  He suggested that Speer move ahead with his memoirs.  In January 1953, Speer began work on his draft memoirs, and over the next year lengthy missives, sometimes written on tobacco wrappings or candy wrappers but most often on toilet paper, made their way to Wolters' office in Coesfeld.  Marion Riesser, who had continued as Wolters' secretary as he began private architectural practice, transcribed these notes into as many as forty closely typed pages per missive, and the draft totalled 1,100 pages.  Wolters objected that Speer called Hitler a criminal in the draft, and Speer presciently observed that he would likely lose a good many friends were the memoirs ever to be published.  Wolters had come to believe that reports of Nazi genocide were exaggerated by a factor of at least ten, that Hitler had not been given credit for the things he did right and that Germany had been harshly treated by the Allies.In the mid-1950s, Wolters quarrelled with Kempf who effectively dropped out of the network for a number of years, adding to the burden on Wolters and Riesser.  While Speer's pleas for his former associate and his former secretary to work together eventually brought about a healing of the breach, this was to some degree superficial as Kempf was aware that Wolters, even then, disagreed with Speer's opinions.  Wolters questioned Speer's readiness to accept responsibility for the Nazi regime's excesses and did not believe Speer had anything to apologise for, though the strength of his feelings on this point was kept from Speer—but not from Kempf and Riesser.Wolters was tireless in his efforts on behalf of Speer and his family to such an extent that his son, Fritz, later expressed feelings of neglect.  For Speer's fiftieth birthday in March 1955, Wolters gathered letters from many of Speer's friends and wartime associates, and saw to it that they made their way inside the walls of Spandau in time for Speer's birthday.  Wolters gave Speer's son Albert a summer job in his Düsseldorf office and a place to stay—in fact, Wolters hosted all six of the Speer children at one time or another.  By prior arrangement, he and Speer tried to get in touch with each other by telepathy one New Year's Eve—but both men fell asleep before midnight struck.Wolters constantly sought Speer's early release, which required the consent of the four occupying powers.  He engaged Düsseldorf attorney, and later state minister, Werner Schütz to lobby high German officials to get them to advocate Speer's release.  Schütz, who refused to ask for his expenses, was unsuccessful even though Lübke, West German President for the last seven years of Speer's incarceration, had worked under Speer.  Wolters had more success fending off denazification proceedings against Speer, collecting many affidavits in Speer's favor, including one from Tessenow whom Speer had shielded during the war.  Those proceedings dragged on for years, and were eventually ended by order of Willy Brandt, a strong supporter of Speer's.As early as 1956, Wolters feared the effect that disclosure of the GBI's eviction of Jewish tenants might have on Speer.  Wolters wrote to Kempf concerning the denazification proceedings, "I am only anxious about the matter of the clearance of Jew-flats in Berlin.  That could be a bullseye.  And this is the point to which the defense should direct itself ..."  In 1964, Speer mentioned to Wolters in a letter that he would need the Chronik as a reference in revising his memoirs upon his release.  Wolter's response was to have Riesser retype the entire Chronik, leaving out any mention of the GBI's involvement in the persecution of the Jews, without telling Speer what he was doing.  Wolters later wrote that he did this to correct mistakes, to leave out extraneous matters, and "above all to delete certain parts on the basis of which Speer and one or another of his colleagues could still have been prosecuted.  The Ludwigsburg Central office for 'war crimes' was still at work and an end of the persecution of National Socialists was not in sight."In April 1965, with only eighteen months left of Speer's sentence, Wolters wrote to him of their prospective reunion, "[I]t will have been twenty years since I saw you last.  What will there be between us old codgers, aside of course from happy memories of skiing tours in the long distant past[?] ... Will you come to me mainly to take receipt of the promised gift I have held for you in our cellar—that long cured Westphalian ham, and those patiently waiting bottles of your favorite nectar: Johannisberger 1937?  Could these things of the senses end up being all that there is between us?  I am so happy that the moment approaches, but my heart is heavy ..."According to Riesser, she thought that Wolters "was frightened of the reality of Speer". However, Kempf thought Wolters wished Speer ill.  Speer was unaware of the depth of Wolters' feelings, and later told his biographer-to-be Joachim Fest that Wolters was the closest friend he had.  Speer added that during the Spandau years, Wolters performed invaluable services for him and that he did not know how he would have survived Spandau without Wolters' assistance.Throughout the latter part of Speer's imprisonment, Wolters was a faithful correspondent, writing lengthy letters to Speer at least once a month, attempting to tell Speer everything that might interest him but nothing that might hurt him.  When Speer invented the concept of his "world wide walk", imagining his daily exercise around the prison yard to be segments in a long walk from Europe through Asia to North America, Wolters supplied Speer with details of what he would "see".  Speer later stated, "In a manner of speaking, Rudi Wolters accompanied me on these walks."  As midnight struck and October 1, 1966 began, Speer was released from Spandau Prison.  His last use of the clandestine message system was to have a telegram sent to Wolters, in which Speer jokingly asked Wolters to pick him up thirty-five kilometres south of Guadalajara, Mexico, which he had "reached" after walking 31,936 kilometres. 
Question: What is the last name of the person who made Fritz feel neglected?
Output: Wolters.