Attending a tour of the Warner Bros. film studio today in Leavesden, England, Kate Middleton wore a polka dot Topshop dress with Ralph Lauren jacket.
The $76 frock sold out within hours of her wearing it, online and in stores.
Despite the Duchess being six months pregnant, the dress is not maternity wear. You wouldn't know it from how perfectly it covered the royal heir(ess).
Seriously. One of the cutest Kate Middleton baby bump photos yet.
This isn't the first time the 31-year-old wife of Prince William has caused clothing to sell out at warp speed, and it's safe to say that it won't be the last.
Most famously, the blue Issa dress she when she announced her engagement in 2010 continued to sell out even after the brand replenished the stock.
Here's hoping Topshop learned from that experience.
For many more of the brunette British beauty's best looks - from before and during her pregnancy - check out our Kate Middleton fashion section!