Sean Sidi, 19, has been missing since May 21, and marking the month of his absence his family held a vigil Sunday afternoon in Golden Gate Park, where he was last known to be. Sidi has now been declared "medically disabled" by a chief neurosurgeon S.F. General, and this may help escalate the SFPD's efforts to find him.

Sidi suffered a fall at the end of last year that left him with a traumatic brain injury, and his family has repeatedly said that he was still quite "fragile" on the day of his disappearance. He left the family's home and went to speak to to a former teacher at his high school at the French American School at Oak and Gough, and his last contact with his father was that afternoon, when he said he was going to Golden Gate Park. After that, his phone apparently went dead. The last "ping" from his phone was near or around Alvord Lake, Stow Lake, or the Inner Richmond.

Searches since May have focused on the park, but have not turned up anything. Sidi, pictured here on Facebook, is 5' 5", 120 lbs., half-Asian, slender, with dark brown hair and eyes and braces on his teeth. He was last seen wearing a black North Face jacket, as pictured above.

Below, his family's appeal for help. Anonymous tips about his whereabouts can be made here, via this website, and non-anonymous ones can be made here.