Michael J. Fox at the 'TODAY' show studio Michael J. Fox at the 'TODAY' show studio on February 05, 2013 in New York, New York (Footage by WireImage Video/Getty Images)

Michael J. Fox and Tracy Pollan at the 71st Annual Golden Globe Awards - Arrivals at The Beverly Hilton Hotel on 2014-01-12 in Beverly Hills, California.

INTERVIEW: Buring Spear says everyone loves Muhammad Ali and Michael J. Fox. at the 2010 A Funny Thing Happened On The Way To Cure Parkinson's at New York NY. (Footage by WireImage Video/GettyImages)

Michael J. Fox at the Spike TV's 'Scream 2010' at Los Angeles CA. (Footage by WireImage Video/GettyImages)

Tom Colicchio and Michael J. Fox at the 2010 A Funny Thing Happened On The Way To Cure Parkinson's at New York NY. (Footage by WireImage Video/GettyImages)

Ricky Gervais and Michael J. Fox at the 2011 A Funny Thing Happened On The Way To Cure Parkinson's - Red Carpet at New York NY. (Footage by WireImage Video/Getty Images Entertainment Video)

k-os on Canada, America, truth, success, fame, Vancouver, Michael J. Fox, Mighty Mouse, A Tribe Called Quest, Bob Dylan, rap music and Black history. Produced by Uncensored Interview / ZenCat Productions. k-os interview (clip 5) on May...

Schuyler Fox, Michael J. Fox, Tracy Pollan, and Aquinnah Fox at the 2010 A Funny Thing Happened On The Way To Cure Parkinson's at New York NY. (Footage by WireImage Video/GettyImages)

Schuyler Fox, Michael J. Fox, Tracy Pollan, Sam Fox and Aquinnah Fox at the 2011 A Funny Thing Happened On The Way To Cure Parkinson's - Red Carpet at New York NY. (Footage by WireImage Video/Getty Images Entertainment Video)

Aquinnah Fox, Sam Fox, Tracy Pollan, Michael J. Fox and Schuyler Fox at A Funny Thing Happened on The Way to Cure Parkinsons at The Waldorf - Astoria Hotel on November 10, 2012 in New York, New York (Footage by WireImage Video/Getty...

Aquinnah Fox, Sam Fox, Tracy Pollan, Michael J. Fox and Schuyler Fox at A Funny Thing Happened on The Way to Cure Parkinsons at The Waldorf - Astoria Hotel on November 10, 2012 in New York, New York (Footage by WireImage Video/Getty...

Michael J Fox leaving Madison Square Garden after the NY Knicks game - Celebrity Sightings in New York on 2014-01-20 in New York City.

Michael J. Fox signs autographs for fans as he departs the 'Late Show With David Letterman' in New York 09/08/11 at the Celebrity Sightings in New York at New York NY. (Footage by WireImage Video/Getty Images Entertainment Video)

Michael J. Fox signs autographs for fans as he departs the 'Late Show With David Letterman' in New York 09/08/11 at the Celebrity Sightings in New York at New York NY. (Footage by WireImage Video/Getty Images Entertainment Video)

WireImage Daily: 11/23/09 (Footage by WireImage Video/GettyImages)

Michael J. Fox arrives at Good Morning America at the Celebrity Sightings in New York at New York NY. (Footage by WireImage Video/GettyImages)

WireImage Daily: 4/15/10 - Spanish Version (Footage by WireImage Video/GettyImages)

WireImage Daily: 4/15/10 (Footage by WireImage Video/GettyImages)

WireImage Daily: 10/20/10 (Footage by WireImage Video/GettyImages)

WireImage Daily: 10/26/10 (Footage by WireImage Video/GettyImages)

WireImage Daily: 10/26/2010 - Spanish Version (Footage by WireImage Video/GettyImages)

Michael J. Fox outside the 'Late Show with David Letterman' studio at the Celebrity Sightings in New York at New York NY. (Footage by WireImage Video/GettyImages)

EVENT CAPSULE CLEAN: Spike TV's Scream 2010, Los Angeles, CA, United States, 10/16/10(Footage by WireImage Video/GettyImages)

INTERVIEW: Connie Britton says she worked with Michael J. Fox on Spin City for four years, she was around when he found out he had Parkinson's. at the 2010 A Funny Thing Happened On The Way To Cure Parkinson's at New York NY. (Footage by...