The conflict began after Yemen's authoritarian president, Ali Abdullah Saleh, was replaced by his deputy, Abdrabbuh Mansour Hadi. However, President Hadi failed to bring political stability in the face of corruption, militant attacks, food insecurity, and the unrelenting loyalty of military officers towards Saleh. In 2014, the Houthi Shia Muslim rebel movement seized control of Saada providence and its near region in the North of Yemen, later taking the capital, Sanaa, which led to Hadi's exile abroad. The conflict grew in 2015 after eight mostly Sunni Arab states (supported by the UK, US, and France) and Saudi Arabia, began air attacks against the Houthis, to restore President Hadi's government. Ever since, both sides have continued armed conflict that has caused the world's biggest humanitarian crisis. About 8.4 million people face starvation and 80% of the population is in need of humanitarian assistance, in addition to the approximate of 400,000 children under five years old dead due to severe acute malnutrition.
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In need of humanitarian assistance: 12.2 million children (est.)
Out of school prior to Covid-19 closures: At least 2 million children.
Children under 5 requiring treatment for acute malnutrition: About 2 million.
Source here.