Another day, another star putting their foot in their mouth on social media… This time, it was Scott Baio and his wife, Renee, who came under fire after he shared a meme suggesting that the Sandy Hook massacre — the country’s third deadliest mass shooting, which claimed the lives of 20 children and six elementary school staff members — was actually a hoax. Things quickly escalated when Nelba Marquez-Greene, whose daughter Ana died in the shooting, got involved and the Happy Days star’s wife resorted to name-calling. Check out the video to see the since-protected tweets.

Since her daughter’s tragic death in 2012, Nelba has become an advocate in the community through The Ana Grace Project — an organization dedicated to promoting “love, community, and connection” for every child — as well as outspoken critic against Sandy Hook “truthers.” Earlier this year, she penned an opinion piece for The Washington Post after Megyn Kelly opted to interview Alex Jones, radio host and noted Sandy Hook denier.

“My daughter, Ana Grace, was killed in the Sandy Hook shooting of December 2012. She will always be six-years-old. She will never give another Father’s Day present to my husband, Jimmy. I wish her death were only a hoax,” she wrote.

“Deniers of this tragedy cause unfathomable pain to families who have experienced catastrophic and public losses. It disrupts the grief process, which is unending. Sometimes, it threatens their physical health and safety… And deniers of tragedy are a danger to all Americans. Victims of tragedy require and deserve our support. Deniers create a distraction that shifts focus from compassion to craziness, that throws sand in the wheels of the action we should be taking to create a safer society.”

After the incident on Twitter, the 56-year-old actor expressed regret for sharing the image on his Twitter page. He explained, “My retweets are not endorsements, but having said that, this is one I wish I hadn’t sent.”