One of the girls
Before smartphones became an inseparable part of our lives, we used to take “selfies” in mirrors, mostly elevator or bathroom mirrors. When this girl was invited to the slumber party, she wasn’t told about the dress code, and she didn’t have matching pajamas like the rest of the girls from her class.
That’s why she wasn’t included in the group selfie, which can really make someone feel left out. These girls were enjoying themselves, having a good time, but they never noticed someone was missing from the photos. Eventually she did appear in the photos, just on in the same way she had hoped.