Similarity is based on note and accord overlap, not molecular analysis.
Differences come from accords and community votes on longevity and sillage.
The main accords of Milk Bar Birthday Cake are sweet and vanilla. It opens with Sprinkles, reveals Frosting at its heart, and dries down to Cake and Vanilla. People reach for it in autumn and winter, mostly by day.
How a perfume unfolds →References: Fragrantica