The main event is planned in London's Trafalgar Square, and speakers include Cox's husband, Brendan Cox, and Nobel Prize laureate Malala Yousafzai. Cox's death shocked the international community and brought the referendum campaign on whether Britain should remain part of the European Union to a standstill. The man accused of killing Cox is said to be Thomas Mair, 52, and he is currently in police custody.
Social media has also been flooded Wednesday with people paying tribute on Cox's birthday. On Twitter, people are using the hashtag "more in common" to raise awareness about the issues Cox cared about. The hashtag was started by organizers of the main event, and they said in a statement:
"Jo believed that there is more that unites us than divides us, and she was killed for those beliefs. She believed in a love that is fierce, brave and humble. Her death has devastated a family, and attacked the ideals that we as a nation most cherish."
Google is also paying tribute; at the bottom of its page was the message "In remembrance of Jo Cox MP."
Perhaps Cox's biggest contribution was on the social issues she advocated for, specifically the plight of refugees, in an especially difficult political climate. As my colleague Ishaan Tharoor has pointed out, Cox spoke in defense of a bill last April to accept 3,000 child refugees that was eventually voted down.
"Who can blame desperate parents for wanting to escape the horror that their families are experiencing? ... Those children have been exposed to things no child should ever witness, and I know I would risk life and limb to get my two precious babies out of that hellhole," Cox said about Syrian refugees.
Even in war-torn Syria, some people have taken notice that it's Cox's birthday and are honoring her work. In the image below, which was posted on Twitter, a man who appears to be in Aleppo, Syria, is holding up a sign that reads "Aleppo grieves for Jo." A vigil was also said to be held at a women's charity center in Syria.
The Labour Party has also been encouraging people to celebrate and honor Cox's birthday:
Cox leaves behind her husband and two kids. On Twitter, her husband urged people to celebrate her legacy.