But while the royal family continue to congratulate the new parents on this amazing next chapter of their lives, their new son's date of birth marks the anniversary of a sad time in royal history.
On February 9th 2002, the Queen's sister Princess Margaret sadly passed away aged 71.
Now, 19 years later, Margaret's great niece has given birth to another royal, growing the ever long line of the monarchy.
While this date marks a sad time for the Queen, welcoming a new baby into the centuries-old family is sure to be a nice circle of life moment for the monarch.
Eugenie and Jack's newborn has become the Queen's ninth great-grandchild - the fourth boy of the pack.
In their official statement, the palace revealed the new bub weighs 8lbs 1oz (about 3.6kgs).
The baby boy is also the first grandchild for Prince Andrew and Sarah Ferguson.
The palace assured royal fans that mother, father and son were all "doing well" and Eugenie further proved she was caught up in all the baby bliss by the sweet snap she shared to Instagram.
Posting a black and white photo of her and Jack holding their newborn's tiny hand, the princess simply captioned the photo, "💙💙💙."
It's a day to go down in a royal history.