Texas congressman Sylvester Turner died Wednesday, months after filling the U.S. House seat of the late Sheila Jackson Lee.

Sylvester Turner, a Texas Democrat who was just sworn into the House in January after previously serving as mayor of Houston, died on Tuesday night.Turner posted on social media ahead of President Trump’s address to the nation and sat in the chamber for the speech.

The cause of death is unclear. Turner took office weeks ago, filling the seat left vacant by the death of Rep. Sheila Jackson Lee.