Prince William, Kate Middleton and Prince Harry celebrated World Mental Health Day 2017 in Buckingham Palace. The Duchess wore Temperley London's Eclipse Lace Collar Dress in Iris.

The A-line dress is "a modern take on the lace dress underpinned by the season's Elizabethan influence". The dress features corded lace, scalloped edges, frilled sleeves and a black velvet neck tie.

Kate Middleton

Kate accessorized with simple black heels, stunning diamond earrings and ring and a black suede clutch from Mulberry. She wore very simple makeup and loose curls.

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge and Prince Harry

Looking for something similar at a significantly lower price? We love...

  • New Look's Mela lace bell sleeve dress which you can buy here for €49.99
New Look's bell sleeved dress
New Look's bell sleeved dress
  • ASOS high neck mini skater dress, below, with lace top can be found here for £45.00
Asos high neck mini skater dress
Asos high neck mini skater dress
  • Jessica Wright's lace bell sleeve bodycon dress, below, can be bought here for £65.00
Jessica Wright's lace bell sleeve bodycon dress from House of Fraser
Jessica Wright's lace bell sleeve bodycon dress from House of Fraser

The last time Kate stepped out in public, she wore a beautiful Prada dress during her visit to The Sunken Garden at Kensington Palace in remembrance of Princess Diana.

Kate Middleton is pregnant with her third child
Kate Middleton is pregnant with her third child

The Duchess, who is pregnant with her third child, has been out of the spotlight as of late due to her battle with Hyperemesis Gravidarum