Penny Thornton told Vogue: "Prince Louis was born on April 23, so his birthday could be close to baby Sussex's, if not on the same day. It's also likely Louis an the new baby will share a Sun-Uranus conjunction, which will make them kindred spirits. That doesn't mean they'll get on, of course."
Penny also went on the reveal what kind of parents Harry and Meghan will be.
"You don't have to be an astrologer to know which parent is going to run the baby show," she explained.
"Meghan will be on it from the moment the baby makes an appearance. And Harry will be the completely doting father, giving way to Meghan on all points. Meghan is a Leo, and Leos rule! Harry is a Virgo, and Virgos love to serve.
"If the baby is an Aries, they're in for a thrilling ride. If a little Taurus emerges, that heavenly smile will hide a steel backbone."