Liza Minnelli spotted looking happy post rehab Credit: INFphoto.com

Liza Minnelli is on the mend! The Cabaret star was all smiles while dining at Lisa Vanderpump’s restaurant PUMP in West Hollywood, Calif., on Sunday, April 19 — just one month after Us Weekly revealed the actress was seeking treatment in rehab for substance abuse.

According to an eyewitness, Minnelli, 69, was sitting at a table on the sidewalk and was happy to mingle with fans, who were coming up to her asking for her autograph.

“She was smiling and signing autographs,” the source tells Us. “She looked fantastic and spirited.”

Restaurant owner Lisa Vanderpump was unfortunately absent from the fun-filled evening. An insider close to the Bravo star tells Us she was at home tending to her husband Ken, who recently had hip replacement surgery.

As previously reported, Minnelli checked herself into a Malibu rehab facility last month. "Liza Minnelli has valiantly battled substance abuse over the years and whenever she has needed to seek treatment she has done so," a statement read to Us at the time. "She is currently making excellent progress at an undisclosed facility."