Brooke Shields, who suffered from severe postpartum depression after the birth of her first child, was concerned that she’d be in the same state after the arrival of her second daughter – but this time around has been "nothing like the first one," Shields tells PEOPLE.

Since Grier Hammond Henchy's April 18 arrival, the only discomfort Shields has felt is the pain from her C-section incision. Although she was prepared to ask for another prescription of Paxil, the antidepressant that helped her recover with daughter Rowan, now 3, she didn't need it this time.

"I was like, 'You know what? I think I'm okay now,'" she said to her doctor, PEOPLE reports in its upcoming issue.

This should come as good news to Tom Cruise, who admonished the actress last year for taking antidepressants. Speaking of Cruise, although Shields and Katie Holmes gave birth on the same day, on the same floor, of the same hospital, at first Shields wasn't even aware that there was another celebrity down the hall.

"Basically, I was being cut in two, so it wasn't the first thing I was going to ask about," says Shields. "I was just glad that everything for me was going well."

One month later, it still is. Shields, 40, and her husband, sitcom writer Chris Henchy, 42, have slipped into a happy routine, quickly adjusting to life with their littlest addition.

"Now it just really feels like a full-on family," says Shields. "I'd be lucky to just have the one, but with two, I realize they'll have each other after we're not here anymore, and to me, that really settles my mind."