'GMA' to kick off 4th anniversary with 40-hour livestream Tuesday

"Good Morning America" is celebrating its 40th anniversary this week.

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The show will go live for 40 straight hours in celebration of the show's 40th anniversary Tuesday starting at 5 p.m.

Robin Roberts and George Stephanopoulos will kick off the live event at 5 p.m.

Watch the 40-hour livestream here.