While Britney Spears and her brother, Bryan Spears, had a ball as they visited places like Mexico and Las Vegas over the past several weeks, an insider claimed the superstar’s sibling has also been spending more time with her in order to ensure she’s surrounding herself with the right people. According to a source, Bryan, 47, is “protective” of the singer and wants to make sure she steers clear of “lowlifes” who have taken advantage of her in the past. Unsurprisingly, Bryan isn’t a fan of his sister’s new boyfriend, Paul Richard Soliz, who has a criminal past, but the blonde beauty has yet to …