Prince William took part in the Colonel's Review at Horse Guards Parade on Saturday, but not everything went as planned.During the rehearsal ahead of The King's Birthday Parade, a member of the Band of the Welsh Guards fainted as William carried out his review in London. In what marked the first time he carried out the review of the Welsh Guards as Colonel of the Regiment, a group of medics rushed to the trombonist's aid as he lay on the ground still holding his trombone.After the trombonist was carried out by stretcher, the 40-year-old Prince of Wales — wearing ceremonial guard attire, a bearskin cap and sword -- praised the soldiers who took part in the rehearsal under «difficult conditions,» as temperatures soared into the mid-80s.