As PEOPLE reports in its new issue, just a day after picking up her newly adopted daughter in Ethiopia, Jolie began to worry something was wrong. Zahara Marley Jolie, already underweight at just 9 lbs., wasn't drinking enough formula.
Jolie took Zahara for a checkup, and wound up spending a week by her daughter's side in a New York City hospital as the baby battled a bacterial infection that, left untreated, could have been life-threatening. (Zahara's mother is believed to have died of AIDS a month after giving birth and her father is unknown.)
Fortunately, after being treated with fluids for dehydration and antibiotics to combat what Aronson diagnosed as a salmonella infection, Zahara left the hospital "happy and gurgling" on July 15 with a clean bill of health. She also gained more than a pound.
Angelina, Zahara and the actress' son, 3-year-old Maddox, then flew to L.A. July 16 to reunite with another recuperating friend: They stayed at Pitt's Malibu estate as he spent the week recovering from a bout of viral meningitis.
Pitt had been with Jolie in Ethiopia when she adopted her daughter. (His malady likely has "nothing to do" with salmonella, says Aronson, who told PEOPLE that Jolie never mentioned Pitt to her.)
Mother and daughter both appeared to be feeling much better this week, when they were spotted in Malibu at a supermarket and toy store and stopping in a Starbucks.
Meanwhile, Pitt also seems to have shaken his illness: He showed up Wednesday at the Beverly Hills Hotel to accept a $250,000 check on behalf of the Film Foundation at the Hollywood Foreign Press Association luncheon.