Their son is the second baby to join the Monegasque royal family this year, and proud Princess Caroline's second grandchild. In March 2013, Charlotte's brother Andrea became a first-time father when his wife Tatiano Santo Domingo gave birth to their son Sacha.
Click on the photo for more of Charlotte and Andrea's baby pictures.
In celebration of the new baby's arrival, we take a look back through the royal family album to Charlotte's own childhood. She was the adored middle child from Caroline's marriage to dashing businessman Stefano Casiraghi. In all the couple had three children before he died tragically young.
Charlotte also has a much younger sister from her mother's later union with German aristocrat Ernst of Hanover.
In this special gallery we have also taken a look back to Caroline's own upbringing in the splendid Prince's Palace that looks out over Monte Carlo.