Watch Birthday Boy for Free: How to Stream the Movie Online at 123Movies. . It is Sjoerd's birthday and his mother has spared no trouble or expense to make this day a pleasurable one. Helped by the au pair, she takes the eleven-year-old kid on a search, where an unfortunate coincidence puts them in the middle of a raid. The criminals take the complete party bunch hostage and then it is a matter of surviving for the birthday boy.