Dianne Guess, 82, of Middletown, died Thursday December 11, 2025 at Hartford Hospital.

She was born in Middletown, the daughter of the late John and Janet (Triblets) Sundell. Prior to her retirement, Dianne was with the Human Resources Department of Northeast Utilities.

She is survived by her son, Michael O'Brien of Simsbury; along with his family; and by her granddaughter Kylie O'Brien.  She was predeceased by her son, William O'Brien; sister, Phyllis Nealon and brother, John "Jack" Sundell.

Dianne grew up in Cromwell and Portland, where she was known by all for her kindness and thoughtful heart. Her greatest passion was cooking; she loved nothing more than trying out a new kitchen gadget or sharing a recipe she had recently discovered. Dianne's happiest moments were spent traveling and game nights with her dear friends—adventures she spoke of often and with great fondness. She leaves behind a family who will forever miss her warmth and her cooking.

Funeral services are private and burial will be at the convenience of her family.  There are no calling hours. To share memories or express condolences online please visit www.biegafuneralhome.com.