Question: Who produce the American Christmas fantasy in which Robert Prosky has a supporting act? 

Context articles: The Santa Clause
Age Isn't Everything
Gremlins 2: The New Batch
The Skeptic (film)
Miracle on 34th Street (1994 film)
John Prosky
Robert Prosky
Lifestories
Mrs. Doubtfire
Broadcast News (film)

The Santa Clause is a 1994 American Christmas fantasy family comedy film directed by John Pasquin.
 It is the first installment in "The Santa Clause trilogy" and it stars Tim Allen as Scott Calvin, an ordinary man who accidentally causes Santa Claus to fall from his roof on Christmas Eve.
 When he and his young son, Charlie, finish St. Nick's trip and deliveries, they go to the North Pole where Scott learns that he must become the new Santa and convince those he loves that he is indeed Father Christmas.
Age Isn't Everything (a.k.a. Life in the Food Chain) is a 1991 comedy film directed by Douglas Katz, and starring Jonathan Silverman, Robert Prosky, and Rita Moreno.
 The film premiered at the 1991 American Film Market, and was consecutively released on video by Live Home Video.
Gremlins 2: The New Batch is a 1990 American comedy horror film, and the sequel to the 1984 film "Gremlins".
 It was directed by Joe Dante and written by Charles S. Haas, with creature designs by Rick Baker.
 It stars Zach Galligan, Phoebe Cates, John Glover, Robert Prosky, Haviland Morris, Dick Miller, Jackie Joseph, Robert Picardo and Christopher Lee; additionally, the film features Tony Randall and Frank Welker providing the voices for two gremlins.
 The story continues the adventures of the creature Gizmo (once again voiced by Howie Mandel), who spawns numerous small monsters when wet.
 In the first film, Gizmo's offspring rampaged through a small fictional town.
 In "Gremlins 2", Gizmo multiplies within a skyscraper in New York City.
 The new creatures thus pose a serious threat to the city should they be able to leave the building, and much of the story involves the human characters' efforts to prevent this disaster.
The Skeptic is a 2009 American suspense thriller film written and directed by Tennyson Bardwell.
 Starring Tim Daly, Zoe Saldana, and Tom Arnold, and featuring Robert Prosky and Edward Herrmann, it depicts the story of an attorney who inherits a seemingly haunted house, though he does not believe in the supernatural.
Miracle on 34th Street is a 1994 American Christmas fantasy film written and produced by John Hughes and directed by Les Mayfield.
 It stars Richard Attenborough, Mara Wilson, Elizabeth Perkins, and Dylan McDermott, and is the fourth remake (and the second theatrical version) of the original 1947 film.
 Like the original, it was released by 20th Century Fox, to mixed to positive reception.
John Prosky is an American film, theatre, and television actor.
 His numerous TV credits include "NYPD Blue", "ER", "Heroes", "Criminal Minds", "True Blood", "JAG", "My So-Called Life", "", "The Practice", "The X-Files", "The West Wing", "Charmed", "24", "House", "Grey's Anatomy", "Veronica Mars", "Fringe," and the web series "Red Bird".
 His film credits include "The Nutty Professor", "Bowfinger", and "A.I. Artificial Intelligence".
 He also contributed voice work to the "L.A. Noire" video game.
 He is the son of actor Robert Prosky.
Robert Prosky (December 13, 1930 – December 8, 2008) was an Polish-American actor and comedian.
 He became a well known supporting actor in the 1980s and 1990s with his roles in "Thief" (1981), "Christine" (1983), "The Natural" (1984), and "Broadcast News".
 Prosky's other notable movies include "" (1990), "Hoffa" (1992), "Mrs. Doubtfire" (1993), "Last Action Hero" (1993), "Miracle on 34th Street" (1994), "Dead Man Walking" (1995), and "Mad City" (1997).
Lifestories is an American medical drama television series that premiered August 20, 1990, on NBC.
 Done in a documentary style with off-screen narration by Robert Prosky, "Lifestories" was an attempt to make an extremely realistic medical drama answering questions like, "Exactly what goes on during the first 45 minutes of a heart attack?"
 "What is it like to be told that you have advanced colon cancer?"
Mrs. Doubtfire is a 1993 American comedy-drama film directed by Chris Columbus and written for the screen by Randi Mayem Singer and Leslie Dixon, who based their story and script on the novel "Alias Madame Doubtfire," written by Anne Fine.
 It stars Robin Williams (who also served as a co-producer of the film), Sally Field, Pierce Brosnan, Harvey Fierstein, and Robert Prosky.
 It follows a recently divorced actor who dresses up as a female housekeeper to be able to interact with his children.
 The film addresses themes of divorce, separation and the effect it has on a family.
Broadcast News is a 1987 romantic comedy-drama film written, produced and directed by James L. Brooks.
 The film concerns a virtuoso television news producer (Holly Hunter), who has daily emotional breakdowns, a brilliant yet prickly reporter (Albert Brooks) and his charismatic but far less seasoned rival (William Hurt).
 It also stars Robert Prosky, Lois Chiles, Joan Cusack, and Jack Nicholson (billed only in the end credits) as the evening news anchor.