"💙💙💙!!" the new mama captioned her post on Tuesday, February 9.
Of course, people were quick to congratulate the royal family-of-three in the princess' comment section. "Congratulations !!! Hope you and the baby boy are doing okay ❤️," one user wrote while another added: "Amazing! Huge congratulations guys 😍 Xxxx."
A third supporter commented: "Ahhhh congratulations to you both 😊."
The Palace confirmed the birth of Eugenie and Brooksbank's child — who is 11th in line to the throne — earlier that day. "Her Royal Highness Princess Eugenie was safely delivered of a son today, February 9 2021, at 8.55am at The Portland Hospital. Jack Brooksbank was present," the statement read.
"The Queen, The Duke of Edinburgh, The Duke of York, Sarah, Duchess of York, and Mr. and Mrs. George Brooksbank have been informed and are delighted with the news," the statement continued. "This is Princess Eugenie and Jack Brooksbank's first child, The Duke of York and Sarah, Duchess of York's first grandchild, and the ninth great-grandchild for The Queen and The Duke of Edinburgh. Her Royal Highness and her child are both doing well."
The lovebirds, both 30, announced the expected arrival of their little boy — who weighed in at 8 lbs. 1oz. — last September. "Her Royal Highness Princess Eugenie and Mr. Jack Brooksbank are very pleased to announce that they are expecting a baby in early 2021," the palace shared at the time.
And although their child will grow up royal, a source previously revealed that the new parents want their son to have a normal life.
"Even if the Queen offered them a title as a gift, it's not Eugenie or Jack’s desire for their child to have a title. Eugenie knows that a title can be a curse as well as a blessing," the insider dished. "Titles really don’t matter to Jack and Eugenie, they just want a happy, healthy child."