What Bracha do you make on the birth of a child? What Bracha is made on a Boy? What Bracha on a Girl? When is this Bracha Made?
It appears that HaTov vehameitiv is said upon hearing "you have a new son!"
And shehechiyanu is made upon seeing your new baby daughter. Rav Moshe Feinstein says your new daughter is certainly no worse than a good friend you haven't seen in a while, which also warrants a shehechiyanu.
The gemara says that you can say Hatov vehameitiv when you have a son. It also says you can say that same bracha on any 'besorot tovot' (good tidings). Both of these rulings are quoted in the Shulchan Aruch (OC 222:1 and 223:1). In my experience, hearing about a daughter's birth is pretty top-quality good tidings.