FAQ

The question is put to the viewer at the end of the movie in the final scene between Lilly and Roy although throughout the movie the scenes, dialog and underlying sexual tones between the two of them also raises some doubt and leaves the viewer asking this very question. In the last scene Lilly is desperate and has resorted to raising this issue directly with Roy as a last resort to grab the money and run.You can see the seed of doubt flash across Roy's eyes which gives Lilly the time needed to make her move. Unfortunately her move results in devastating consequences that no one saw coming including Lilly.

So either she was telling the truth or lying but the intention was to throw Roy off his game and give Lilly the upper hand. There is also the possibility that Roy was adopted but I think this is a long bow to draw.

In reality it is most likely Lilly is Roy's mother and she merely used this as a tactic to get her grubby little hands on Roy's hard earned money. Although Frears never out rightly tells the viewer this is so. The closest we get is where Lilly tells Bobo she has a son in an earlier scene.