Later they played another concert on 18 September 2011 during the I'm with You World Tour. In 1998 Irish rock band U2 brought their PopMart Tour to South America and performed Mothers of the Disappeared with the Mothers of the Plaza de Mayo, the mothers of the children who had disappeared under the Argentinian and Chilean dictatorships, brought on stage. The band returned again for their Vertigo Tour in 2006 to film what would become U23D, the first live-action, 3D digital film.