What to know now:

1. Nine to appear onstage: The next Republican debate will be held Tuesday in Las Vegas, and CNN, the debate's sponsor, has announced the line-up.  Featured on the stage for the main debate will be: Donald Trump, Ben Carson, Ted Cruz, Marco Rubio, Jeb Bush, Carly Fiorina, Chris Christie, John Kasich and Rand Paul. The early debate will feature Mike Huckabee, George Pataki, Rick Santorum and Lindsey Graham.

2. Planned Parenthood suit:

Attorneys for Planned Parenthood have filed suit in Ohio against what they say is the state’s effort to block abortion services there. The suit is asking the court to issue a restraining order and a preliminary injunction  against the state's attorney general after he said he intended to file an injunction that would block the group from disposing of fetal remains in landfills.

: The Los Angeles Sheriff’s Department defended the shooting of a man this weekend, saying he was brandishing a gun and had fired several shots before he was killed by a deputy. On Sunday, the sheriff’s department displayed photos and a video which appeared to show Nicholas Robertson with a gun, firing six to seven shots in the air on a residential street prior to walking toward a shopping district on Saturday. He entered one business displaying the gun, authorities say, and didn’t respond to a request from sheriff’s deputies to drop the weapon.

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4. Twitter hacks:  Twitter is warning some users that "state-sponsored" hackers may have tried to gain information from their accounts. According to one of the users warned, Twitter said the hackers may have been trying to get email addresses, ip addresses, or phone numbers from accounts. Twitter has not commented on the warnings, but the notice said hackers had targeted a "small number of accounts."

5. “Freak Show” actress dies

: Rose Siggins, who played Legless Suzi on "American Horror Story: Freak Show," died this weekend, according to her manager. Siggins was born with sacral agenesis, a rare genetic disorder. Her legs were amputated when she was 2 because of the disorder.  Siggins was 43.

And one more

Taylor Swift was giving the present on her 26th birthday Sunday

. Apple Music will debut the "1989 World Tour Live" concert video, on Dec. 20, Swift announced this weekend.

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In case you missed it

He’s baaaaack!