متن اصلی - ایتالیایی - Buongiorno stella.Oggi è il compleanno di una...

The meaning of stella here is not star and I don't think is a person name either (though there is a name Stella). It's a common way to say darling, sweetie, my love, etc...

You may be right as if it was a name, it'd be featured with capital letters at its beginning (though a lot of people forget to use capitals when typing a name, as I could notice many times here). I will edit the French version using "ma chérie", which is the most commonly used. Thanks for this notification, apple!