Britain's Catherine, Duchess of Cambridge, together with runner Alex Stanley, puts a Heads Together headband onto the Kensington Palace post-box ahead of a reception for Team Heads Together, at Kensington Palace on April 19, 2017 in London. Mental health campaign, Heads Together is the Charity of the Year for the Virgin Money London Marathon which will be run on April 23, 2017. / AFP PHOTO / POOL / Chris Jackson (Photo credit should read CHRIS JACKSON/AFP/Getty Images)

Britain's Catherine, Duchess of Cambridge, together with runner Alex Stanley, puts a Heads Together headband onto the Kensington Palace post-box ahead of a reception for Team Heads Together, at Kensington Palace on April 19, 2017 in London.
Mental health campaign, Heads Together is the Charity of the Year for the Virgin Money London Marathon which will be run on April 23, 2017. / AFP PHOTO / POOL / Chris Jackson        (Photo credit should read CHRIS JACKSON/AFP/Getty Images)