Beverly Hills cast member Camille Grammer tweeted, "My sympathy and condolences go out to Taylor and Kennedy. My thoughts and prayers are with them."
Adrienne Maloof, also of the Beverly Hills cast, tweeted, "My heart goes out to @TaylorArmstrong and Kennedy during this devastating time. You will be in my thoughts and in prayers."
New Beverly Hills cast addition Dana Wilkey told ET, "My condolences go out to the Armstrong family, I am shocked and devastated, I am here for Taylor Armstrong and Kennedy Armstrong in any capacity that they need me and will do anything in my power to support them as they move through this difficult time."
Meanwhile, Bravo producer Andy Cohen wrote via Twitter, "I am so very sad about today's news. My prayers and thoughts are with Taylor Armstrong and her family."
Former New Jersey housewife Danielle Staub tweeted "@TaylorArmstrong love and prayers to you and your family ~ I pray your privacy will be respected in this great time of need!"
Jacqueline Laurita, also of New Jersey retweeted the following tweet, "Thoughts & prayers out to @TaylorArmstrong & her daughter, Kennedy."
Nene Leakes of the Atlanta Housewives cast, tweeted shortly after the news broke, "My dear friend! My heart goes out 2 u! I'am here 4 u," but it wasn't clear that the tweet was related to Armstrong's death.
Ramona Singer of the New York Housewives wrote, "My prayers and thoughts go out to Taylor Armstrong and her family."
Peggy Tanous of the Orange County cast tweeted, "I'm very saddened by the news of Russell Armstrong. My thoughts and prayers are with Taylor and Kennedy and the family."
A spokesperson for Bravo told ET, "All of us at Bravo are deeply saddened by this tragic news. Our sympathy and thoughts are with the Armstrong family at this difficult time."