premise: Abat had urged the military and the public to support calls for the ouster of Arroyo, who survived an impeachment vote in the legislature in September over allegations she cheated to win the May 2004 presidential election.
  Abat failed to rally popular support and the military said they stayed loyal to Arroyo, who survived a military uprising in 2003.
  Abat's son, a middle-level officer in the Philippine Army, was relieved of his post as deputy commander of a brigade deployed north of Manila, the military said Thursday.
  Colonel Victor Abat was accused by superiors of sending mobile telephone text messages that supposedly urged other military officers to join acts of "destabilization" that the military would not specify.
  "I have deemed it proper to relieve him because he had been spreading text messages enjoining officers and men of the army to join the destabilization move," said army chief Lieutenant General Hermogenes Esperon.
   Why was Abat's son relieved of his post as deputy commander?
hypothesis: spreading text messages enjoining officers and men of the army