Robert Pattinson and Kristen Stewart spent Thanksgiving in London with his family.

The low-key couple were spotted checking in at Heathrow airport on Friday for a flight to New York where they happily queued up with other passengers before taking their seats in first class.

"Look who's on my plane!!! Robert Pattinson and Kristen Stewart!! We just arrived at the same time they were behind me in the line!" one excited fan posted on Twitter.

The trip to London comes after it was revealed 26-year-old Robert's older sisters Lizzy and Victoria have finally forgiven Kristen, 22, for cheating on their brother with married director Rupert Sanders. "It was really important for Kristen to win back the love and trust of Rob's family, and she has done just that. They are all back on really good terms -- even better than before. Kristen reached out to Rob's sisters and expressed how sorry she was. They are proud of how far she has come and they know she has been treating their brother like gold," a source said.