Socialite mom Nicole Richie has been hospitalized with pneumonia.

The 28-year-old — who gave birth to son Sparrow in September — bowed out of the Nov. 10 launch of her House of Harlow jewelry at Bebe in L.A., citing illness. On Sunday, Nicole Tweeted that she was feeling ill, writing “ok cold, it’s been 6 days.”

The 28-year-old daughter of singing legend Lionel Richie checked herself into Los Angeles’ Cedars-Sinai Medical Center after her symptoms persisted for several days. But fans have been warned not to worry – Nic is responding well to treatment and is expected to make a full recovery.

“Nicole has checked into Cedars-Sinai where she is being treated for pneumonia,” a rep for the former Simple Life star said Wednesday. “She is doing well.”

Nicole and BF Joel Madden also have a daughter, Harlow, who 22 months.