The advertising watchdog received 22 complaints from parents about the screening of the ad, created by Framestore, before the U-rated family film. Nine of those who complained said their children had been upset by the ad, which called for viewers to help in the search for the missing toddler by downloading and displaying a poster.
Despite the complaints, the ASA said that the ad was designed to "maintain public awareness" of the toddler's disappearance and that those attending the screenings, including children, were likely to already be aware of the high-profile story.
In its ruling, the ASA said: "We considered that because it highlighted in a non-sensationalist way a well publicised issue in an attempt to find a missing child, the ad was not unsuitable to be shown before a film with a U classification, was not socially irresponsible and was unlikely to cause undue fear and distress."