Patricia Dianne Krenwinkel is an American murderer and a former member of the Manson Family. During her time with Manson's group, she was known by various aliases such as Big Patty, Yellow, Marnie Reeves and Mary Ann Scott, but to The Family she was most commonly known as Katie.

Krenwinkel was a participant in the murders on August 9, 1969, at 10050 Cielo Drive, home of actress Sharon Tate and her husband, director Roman Polanski. After stabbing Abigail Folger, Krenwinkel went back inside and summoned Tex Watson, who also stabbed Folger. During her trial, Krenwinkel said, "I stabbed her and I kept stabbing her." When asked how it felt, Krenwinkel replied: "Nothing, I mean, what is there to describe? It was just there, and it was right."

Krenwinkel participated willingly in more murders the following night. Krenwinkel recounted during her December 29, 2016 parole hearing the events of the night of August 10, 1969. Along with Manson, Watson, Atkins, Clem Grogan, Leslie Van Houten, and Linda Kasabian, Krenwinkel went to the home of Leno and Rosemary LaBianca where Krenwinkel, Watson, and Van Houten murdered the couple.

When later questioned, Krenwinkel claimed the only thing going through her mind at the time was that "Now he won't be sending any of his children off to war." Before hitchhiking back to Spahn Ranch, the trio stayed a while in the LaBianca home — eating food, showering, and playing with the LaBiancas' two dogs.

Following the 2009 death of fellow Manson cult member Susan Atkins, Krenwinkel is now the longest-incarcerated female inmate in the California penal system.

Krenwinkel's personal CDC 'Golden Girl' laminated 'credit card style' custody level B inmate I.D. badge issued on 8/10/2013 (the Golden Girls program at California Institution for Women is geared toward addressing the emotional and physical needs of the older population. Any inmate aged 55 or older is eligible to be identified as a GG and participation is voluntary).
Affixed to the back of the I.D. is Krenwinkel's ducat pass/assignment card dated 4/26/2014 (Krenwinkel was in charge of the puppy program which trains K-9's for service to disabled people).
The badge is made of hard plastic and was laminated at the time of issue by California Dept of Corrections. We obtained this ID badge directly from an associate of Ms. Krenwinkel.