Good morning, NBC News readers.

House Democrats demand to see special counsel Robert Mueller's 300-page report, the Brexit day that wasn’t arrives for the U.K. and an opening day record for the Dodgers.

Here's what we're watching today.

Angst and anger reign on the day that Brexit wasn't

Today was meant to be the day when Britain's Brexit mayhem finally reached a moment of certainty.

For exactly two years, March 29, 2019, has been seared into British minds as the date their country would finally leave the European Union.

Instead, that milestone has been postponed. British lawmakers continue to disagree and dither, failing time and again to reach an agreement on how exactly this divorce should work.

Having suffered two crushing defeats already, Prime Minister Theresa May is set to ask Parliament today for a third time to support at least part of the plan she has negotiated with the E.U.

This vote could prove decisive. But one way or the other, months of chaos over Brexit have revealed the deep differences that divide British society.

And it's inspired a clutch of protesters to stand in front of the Palace of Westminster day in and day out — whistling and cheering. It can sometimes feel like a party is going on, and not a painful and profound political realignment.

Adam Maida / for NBC NEws

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DHS will ask for sweeping authority to deport unaccompanied children

Department of Homeland Security Secretary Kirstjen Nielsen will also ask Congress for more funding for detention beds and the ability to hold families longer than currently permitted, according to a copy of the request obtained by NBC News.

Since February, Customs and Border Protection has seen a jump in the number of undocumented immigrants trying to cross the U.S. border each day. Crossings recently hit a 13-year high.

The latest symbol of the Trump administration's struggle to keep up with the surge of migrants is a chain link enclosure under a bridge in El Paso, Texas.

Officials have said the Border Patrol is holding immigrants in the makeshift cell because they can’t keep up with screening the hundreds of immigrants coming to the border daily and the thousands arriving weekly.

Meantime, asylum-seekers stuck waiting in Tijuana, Mexico for U.S. court hearings to decide their fate are fearing for their lives as record violence rocks the city.

More than 2,500 people were killed in Tijuana last year and there have been 488 murders so far this year, according to local reports.

“It feels like they are cutting off your life, the hope of continuing to live,” said R.T., an asylum-seeker from Guatemala who told a U.S. immigration judge that he was afraid to go back to the border city.

Central American migrants wait for food in a pen erected by U.S. Customs and Border Protection in El Paso, Texas. Cedar Attanasio / AP

Democrats want the full Mueller report — but they are increasingly worried their efforts will be stymied

We've now learned that special counsel Robert Mueller's report to Attorney General William Barr is over 300 pages long, according to a Justice Department official.

The length of the report suggests Mueller included substantial evidence to back up his conclusions on Russian interference in the 2016 election — and adds to questions about Barr's brief four-page summary.

House Democrats have made it clear that they want to see the full, unredacted report. But according to a briefing with reporters yesterday, they are increasingly worried that the attorney general will not comply with their request — setting them up on a collision course with the Justice Department next week.

Kim showered Trump with flattery in letter before Hanoi summit

North Korean leader Kim Jong Un heaped praise on President Donald Trump in a letter to the White House before their summit last month in Vietnam, while making clear he wished to negotiate only with the president and not his envoys, current and former U.S. officials told NBC News.

The letter appeared aimed at cutting out the U.S. envoy to North Korea, Stephen Beguin, and Secretary of State Mike Pompeo, in the discussions on the regime's nuclear and missile arsenal, while seeking to appeal to the president's ego, said one current and two former U.S. officials familiar with the matter, who spoke on condition of anonymity

"It was about flattery," said the former U.S. official.

President Donald Trump speaks during a dinner with North Korean leader Kim Jong Un in Hanoi. Evan Vucci / AP file

The Week in Pictures

Southwest Airlines Boeing 737 MAX aircraft are parked at Southern California Logistics Airport on March 27, 2019 in Victorville, California. Southwest Airlines is waiting out a global grounding of the MAX 8 and MAX 9 aircraft at the airport. Mario Tama / Getty Images

Southwest Airlines planes wait out a global grounding of Boeing 737 MAX 8 and Max 9 on a tarmac in California. See more of the most compelling images from the last week. (Photo: Mario Tama / Getty Images)

Plus

Trump reverses course on Special Olympics funding cut after Betsy DeVos comes under fire.

Wells Fargo CEO resigned abruptly Thursday as the scandal-ridden bank took another stab at putting its problems behind it.

Two people have died at the Grand Canyon in separate incidents this week that included one man stumbling over the edge of the rim while trying to take pictures.

Is there a method to March Madness?

THINK about it

There’s a growing chasm in America between the top one percent and the gold-plated group that has pulled away from them — the .01 percent. The college admissions scandal is an example of what happens when America's rich feel threatened by the superrich, writes cultural historian Lynn Stuart Parramore.

Science + Tech = MACH

Alcatraz may be best known as the infamous federal prison that held notorious criminals like Al Capone in the first half of the 20th century. But new research reveals Civil War-era military fortifications under the former penitentiary in San Francisco Bay.

Live BETTER

Overworked and have no time for yourself? Play hooky – or what some call a “productivity cheat day” — and re-energize.

One fun thing

Yesterday was a glorious day for all baseball fans — but particularly if you're a Dodgers fan.

The Dodgers set an MLB opening day record with eight home runs in their romp against the Diamondbacks.

Los Angeles' outburst wasn't just a record for Opening Day — it was just the 25th eight-homer game since 1908, according to Baseball Reference.

They closed out the game at home in Dodger Stadium with a 12-5 win over Arizona.

The Dodgers Corey Seager hits a home run during the fourth inning. Kevork Djansezian / Getty Images

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