Credit: Angela Weiss/Getty Images; Marc Stamas/Getty Images

Real Housewives of Beverly Hills star Lisa Vanderpump is taken aback by the sudden engagement of Kelsey Grammer to his 29-year-old girlfriend Kayte Walsh. (On Monday, Grammer's rep told that the duo had "been engaged for a while.)

"Kelsey Grammer engaged?" Vanderpump Tweeted Tuesday. "Did I miss something?"

Grammer, 55, hasn't yet officially divorced Camille, his third wife and Vanderpump's Real Housewives costar. "Don't you think you should get divorced first?" Vanderpump sniped. She then added: "Just take one step at a a game of chess,that way fewer mistakes and no regrets."

Indeed, the Frasier star filed for divorce after 13 years in July, and immediately stepped out with Walsh. (She sadly had a miscarriage in September.)

Camille, 41, even conjectured to the New York Post that her husband (and father to her two kids) got her booked on the Bravo series so he could cheat with Walsh while he starred in a Broadway show in NYC: "Looking back, maybe he wanted to keep me preoccupied in California while he was off having his affair in New York...I think [Real Housewives] was more Kelsey's agenda."