United Kingdom, Oct. 3 -- National Lampoon's Animal House star Mary Louise Weller has died at the age of 79.

The actress, who played Mandy Pepperidge in the 1978 comedy-drama film, passed away after a short illness on Thursday (01.10.26) - a day before her 80th birthday, her longtime partner Michael Roy Curtis announced, per The Hollywood Reporter.

Mary's close pal David Marks confirmed her death on Facebook with an emotional tribute, which read: "It is with great sadness that I share the devastating news of the passing of our dear friend, Mary-louise Weller.

"Beautiful Mary, friend, actress, model, equestrian, passed away quietly. (sic)"

Many paid tribute to the entertainer in the post's comments section, as one penned: "What a Beaut...