The closeup shot of the Screen Digest magazine resting against the pillow on the chair features a photo of Carole Lombard, but the long shot features a photo of a different actress. (possibly deliberate)
The binding style of Nicol's childhood Hardy Boys book, "The Secret of the Caves", was not in use until 1951. Prior to that they were issued in a brown binding.
The sound from the phonograph in Alex's old bedroom is for the song "Lady In Red". However, a closeup shot of the spinning turntable reveals the label of the record, which reads "Lady Be Good" performed by Buddy Crawford, which is a different song.