
Brad Pitt knows kids - which is why he's sure that his daughters are not going to like his new movie World War Z.
And he believes he knows why!
It's because Selena Gomez isn't in it! Ha!
According to Brad:

We don't know if you've heard, but Selena Gomez is a BIG sister now!
Her new baby sis' name is Gracie Elliot Teefey, and Selena is overjoyed about it!
Her enthusiasm is so obvious from this message Selena tweeted:

Why hello there big sis!!
Selena Gomez spent some quality time at the hospital in Northridge yesterday as she joined her mother Mandy Cornett and her stepfather Brian Teefey as they welcomed her new baby sister to the world!
But after a long and emotional day of baby birthing, Selenita looked absolutely EXHAUSTED!
Luckily, there was a car waiting for her right outside so she could head home for some much needed rest and relaxation!
Based on the Uggs and the comfy sweats she's wearing, we're guessing she passed out as soon as her head hit the pillow!
Better get some sleep, Selena! We're sure your little sister will keep you VERY busy over the next few days!!
[Image via AKM-GSI.]

It looks like Selena Gomez's family just got a little bit bigger!
The Come And Get It singer announced on Mother's Day that her mom Mandy Cornett was expecting her first child with her husband Brian Teefey, and last night she gave birth to a beautiful baby girl!!
Selena's BFF Demi Lovato was one of the first to hear the exciting news, and she took to Twitter to congratulate her:

We loved seeing the twitpic Selena Gomez shared for Mother's Day!
The Spring Breakers star looked so happy about momma Mandy Cornett's new baby bump!
In fact, gurl was so excited, it seems she took a bunch more photos of the two of them together- some selfies just for her!
Ch-ch-check out the pics (below) to see Selena and Mom say cheese!
Look how stoked Selena is! So cute! We're surprised gurl was able to stop snapping pics long enough to take a pic! LOLz!
[Image via Igor Benhuy/Erika Barros/SelenaGomez.com.br.]

Selena Gomez may be single, but that's not going to stop her family from growing!
The Spring Breakers star celebrated Mother's Day by sharing some good news with all her fans! She tweeted:

What did U get your mom for Mother's Day? Did you give her a hug from Justin Bieber onstage at one of his concerts?
If not, you totally lose! Because that's just what the Biebs gave Pattie Mallette!
Here's what she tweeted about her baby boy's A-DORABLE gesture: