Sandra Bullock shows off her children in Peoples Magazine

Congrats to Sandra Bullock ... she's the new mom of a 3 1/2 year old girl, and she just got one of most unique Hollywood introductions we've ever seen.

Sandra's announcement about adopting Laila is People's new cover story -- and there's an adorable family shot of Mom, daughter, and big bro, Louis. It's interesting though ... what you don't see is Laila's face.

The cover ONLY shows the back of her head. There's a bunch of pics inside the mag too -- but not a single one shows the cute little girl's full face. It seems like it was done on purpose, but it's unclear exactly why. Maybe privacy?

Either way... mazel tov!