By Jen Heger - Breaking Celebrity News Assistant Managing Editor

The Florida State Attorney's Office has prepared a subpoena for Trayvon Martin's girlfriend, who was on the phone with him in the moments before the unarmed African American teen was shot and killed by George Zimmerman, to appear in front a grand jury that will be impaneled on April 10, to determine if the neighborhood watch captain should be charged with murder, Breaking Celebrity News is exclusively reporting.

As we previously reported, Martin was gunned down by the neighborhood watch vigilante who had called 911 to report that the teenager was acting suspicious. Even though the 911 dispatche