Baby Mia was just born 5 minutes before this video was taken, but little Sierra really wants her to attend her birthday party, which just so happens to be the very next day. So when Sierra finds out that Mia probably can't make it, she's pretty upset.
Mom tries to reason with Sierra, explaining, "But honey, baby — Mia was just born today, so I don't think she can come to your birthday party tomorrow," but Sierra doesn't seem to care.
Even when mom reminds Sierra that all her other friends are going to come, and the party was is going to be great, Sierra sees pretty much inconsolable.
That is, until she has an important realization — Mia could always go to next year's birthday!