Grandmother Who Killed Kids Was 'Sick'
PHOTO: Two missing children, Ashton and Alton Perry, and their grandmother, Debra Denison, were found dead Feb. 26, 2013 in a vehicle police were searching for during an Amber Alert in Connecticut.

A Connecticut grandmother who was supposed to pick up her two grandchildren from day care and take them home so the 2-year-old could celebrate his birthday with cupcakes and presents, instead drove the boys to a nearby town and killed them, and herself, state police said.

Two hours after an Amber Alert was issued for Alton Perry, who turned 2 on Tuesday, and his brother, 6-month-old Ashton Perry, police found the children and their grandmother, Debra Denison, 47, dead in the woman's car in Preston, Conn.

Police are awaiting the official results from an autopsy, but a gun was found at the scene. Police believe Denison shot the boys and then turned the gun on herself.

The children's mother, Brenda Perry, posted to Facebook on Monday that she was "so excited, making mini cupcakes" and planned on giving Alton Play-Doh for his birthday.

Early this morning, Perry posted again, writing: "Thank you for the prayers. ... My boys are in an amazing place, we got a few great angels watching over us."

Perry also wrote that "my mom was sick."

The Associated Press reported that Denison had bipolar disorder, and that family members had said that Denison also had other mental health problems.

Denison had permission to pick up the boys from Kidds & Co. day care center in North Stonington. When she retrieved them from day care she was carrying a handgun, state police told ABC News.

An employee at Kidds & Co, would not comment.

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