Britney Shaved Head After K-Fed Threatened To Drug Test Her Hair?

OK! magazine reports Kevin Federline was at estranged wife Britney Spears’ Malibu mansion on Friday (February 16) when she arrived home from rehab, and a blowout between the exes broke out. “They had a huge argument,” OK!’s Rob Shuter tells ‘Extra’. “Kevin threatened Britney that he was going to have people test her hair to find out exactly what she’s been up to. She was so scared. That was what made her have her head shaved.”