Continuity mistake: Midway through the episode, the Seer is looking through the sisters' photo album. Several of the photos actually include everyone who was present for the events depicted, leaving nobody to take the photo. And since the events were shown in various episodes, we know that no photo was taken at those times by any automated method.
Visible crew/equipment: While Leo and Piper are at the photography studio with their kids the Avatars appear, and in the shots facing the Avatars the red tape mark is visible on the floor, in front of Avatar Alpha. (00:01:10)
Answer: "Hush, Hush, Hush" Paula Cole.