Japan has reportedly hired singer Pikotaro, whose song 'Pen-Pineapple-Apple-Pen' went viral in 2016, to sing for US President Donald Trump and Japanese Prime Minister Shinzo Abe during Trump's Japan trip. Interestingly, a video showing Trump's granddaughter Arabella singing along to the 45-second song, which had reached No 1 on the Billboard Japan Hot 100 chart, went viral last year.