As for Middleton's own children, Princess Charlotte, Prince George, and Prince Louis, are "doing well, " and feeling pretty festive.
"They’re getting excited for Christmas time, because they’ve started all their Christmas songs and the Christmas trees are going up," she tells listeners in a video shared on Instagram.
"And Louis’ getting bigger," she continued. "I can’t believe he’s like seven months, he’s getting to be a big boy."
When asked if she was excited about Markle's baby news, which was announced last month, Middleton replied with a resounding "Absolutely!"
"It’s such a special time to have little kiddies," she said. "And a cousin for George and Charlotte, as well, and Louis. It’ll be really special."
The cousin is due in Spring 2019, and the sex is still unknown. Markle had to take a step back from some of her public duties in order to rest for the pregnancy. Prince Harry warned spectators at an Invictus Games event that "being pregnant takes its toll," and, at a different event, Markle said it felt like "jet lag."
Watch the video of Kate Middleton below!
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#news Kate talking about Meghan and her new baby! Says she's happy for Meghan and to have a cousin for George,charlotte and Louis is special! So cute 😩💗 by the champ @2cool_4school_2lame_4fame . . The Duke and the Duchess of Cambridge were in Leicester today paying tribute to those who tragically lost their lives in a helicopter crash.