
Britney Spears isn't estranged from all of her relatives these days -- she's still got her brother, Bryan Spears, in her corner ... who's actually with her in Mexico as she parties it up.
The pop star shared a brief sneak peek at a recent getaway south of the border she was on -- or still be in the middle of -- Thursday by posting a video that shows her having a good time with her older bro ... and from the sounds of it, they might be knocking back drinks.

In the clip ... Britney can be seen filming a group of musicians, but then there's a jump cut of her standing next to Bryan in the middle of a town, and he says -- "Let's go to the bar."
There's another cut that shows Britney and Bryan inside some kind of rental, with Bryan walking around in an oversized coat that Britney compliments -- likening him to Elvis.

Later, we saw Bryan leaning over a table with a bunch of plates of food in front of him -- and Britney jokingly notes he must be famished. Her caption to this video reads, "After the bar with my brother !!! Well I guess he thought he was Elvis ðĪ·ââïļðĪ·ââïļðĪ·ââïļð·ð·ð·ððð !!!"
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