The pair were in attendance to launch the Kings Cup Regatta at Cutty Sark, Greenwich, London.
Kate wore a nautical look to fit the event, which had a large price tag.
She addressed the new royal baby. MSN reported the Duchess said: “It’s such a special time and with Louis and Charlotte just having had their birthdays, it’s such a great time for Meghan Markle to have a baby.
“And yes, spring’s in the air and everything so it’s pretty great. As William said, I look forward to meeting him [Baby Sussex] and finding out what his name is going to be.
“So it’s really exciting for both of them. And I’m wishing them the best in these next few weeks. It’s always a bit daunting the first time around.”
Looking smart for the event, Kate wore wide-legged trousers with white buttons.
They are the L.K.Bennett Parker Button Waist Trousers in Midnight Blue, which cost £150.00.
She added a Breton striped top, and wore a red suede clutch bag, £350 from Emmy London.
One her feet the Duchess of Cambridge wore Gianvito Rossi Piper 85 suede pumps, £510.
One Twitter user wrote: “Is Kate wearing trousers? Good to see her mixing it up more.”
Kate wore a pair of Princess Diana’s earrings, a favourite of William’s wife.
The stunning sapphire and diamond pieces match her iconic engagement ring.
Deborah Papas Gemologist Prestige Pawnbrokers of Channel 4’s Posh Pawn told Express.co.uk: “The Duchess of Cambridge wears a lot of blue and her engagement ring with the beautiful cornflower blue sapphire gives reciprocal compliments to her outfits.
“The diamond and sapphire earrings that match her ring were also from Prince William’s mother collection, the late Princess of Wales, and she had them as studs.”
So just how much are they worth?
The expert said: “It is difficult to estimate the value without closer inspection but on the assumption the sapphires are of the same source, Sri Lanka (still referred to as Ceylon in the trade), they could be worth as much as £35,000.”
What parenting techniques has Kate Middleton picked up from Diana?
Although Diana was a first-time mum, she took to it naturally, according to Judi James.
She revealed: “Diana may have been a very inexperienced bride and wife but her work in a nursery prior to her engagement to Charles meant her body language as a mother reflected a sense of confidence and ease.
“Diana was super-tactile, although she could be firm as well as besotted, always showing signs of awareness that she was training a future heir to the throne.”
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