The CEO of a major hospital is confirming that Apple’s health team has made yet another secretive hire: Rajiv Kumar, a top doctor who specializes in treating kids with diabetes. Kumar made headlines in the fall of 2015 by creating a HealthKit-enabled diabetes monitoring system for young patients at Lucile Packard Children’s Hospital at Stanford University.

Kumar’s former employer, Lucile Packard Children’s Hospital CEO Christopher Dawes, says Kumar will keep a part-time appointment at the hospital. “We can’t compete with companies like Apple, Google, and Facebook when they really want one of our own,” he tells Fast Company in an interview.

Rajiv Kumar Photo: via Stanford

Apple did not respond to a request for comment.

With his HealthKit pilot application, Kumar used Apple’s software to help his patients aggregate important health data such as their blood sugar levels, and share it via their iPhone with caregivers and medical professionals. To avoid getting overwhelmed with his patient’s data, Kumar would receive a bi-monthly report on overall trends. It might show, for instance, if a patient had consistently low blood sugar overnight.

In the past few years, the iPhone maker has recruited a team of medical experts to help guide its strategy as it moves into health care. Its team currently includes Divya Nag, a former biotech entrepreneur, and Mike O’Reilly, an anesthesiologist who runs the ResearchKit platform. Apple has not disclosed the total number of employees who work on its health care products and services.

It’s not clear whether Kumar will continue to work with HealthKit or contribute to another service. The company has also released ResearchKit and more recently, CareKit.