Kristen Stewar [ @Kstew_Private ] Steps Out in Robert Pattinson's Shirt

Kristen Stewart may not have held onto Robert Pattinson after the Rupert Sanders affair broke, but she definitely held onto some of his clothes!

The actress is set to make her first red carpet appearance since those controversial photos surfaced tonight at the Toronto Film Festival ... and last night she popped up at LAX for her flight to Canada wearing one of Rob's old shirts.

K-Stew was photographed in a shirt saying "Irie," a Jamaican phrase meaning one is at peace or feeling great ... the same t-shirt Rob was photographed wearing back in July 2011 (right).

At this point nobody knows if Rob and Kristen have completely severed ties or if they're still talking/dating ... and it might be a while until we ever know for sure.

The two never confirmed they were actually a couple until Kristen publicly apologized for cheating on him and they've been pretty good at staying light-lipped about the whole affair since.