Start your week smart: These are the stories to know

(CNN)Happy (really cold) New Year and welcome back to reality in 2018. If you ate and partied your way through the holidays, you may have missed some newsworthy moments. Here's a quick rundown to start the first week of the year smart:

-- President Trump's first tweet of the new year took a swipe at Pakistan.
-- At least 12 people died in Iran as a fifth day of protests swept the country. President Rouhani called for calm and downplayed the unrest.
-- In his annual New Year's Day address, North Korean leader Kim Jong Un held out a rare olive branch to South Korea.
    -- A New Jersey teen is in custody after four people, including his parents and his sister, were killed on New Year's Eve.
    -- A New York family of five are among 12 people killed in a small plane crash in Costa Rica.
    -- The Colorado gunman who on Sunday killed a deputy in a Denver suburb was an Iraq deployment veteran.
    -- There's still a (very slim) chance to win both the Powerball and Mega Millions prizes, which now have reached a combined total of $783 million.
    -- New York City's deadliest fire since 1990 was started by a 3-year-old playing with a stove.
    -- Californians lined up to buy pot after the state became the latest to legalize recreational marijuana.
    -- Reese Witherspoon, Shonda Rhimes and Meryl Streep are among the powerful women in the anti-harassment group Time's Up.
    -- Someone forgot Mariah's hot tea. And the first meme of the year was born.