PORT JEFFERSON, N.Y. (CBSNewYork) — A Long Island mom is facing several serious charges Saturday after police say she gave her four-year-old son a marijuana-laced brownie.

Investigators say the mother, 29-year-old Sydney Marquez, is a known drug dealer in the area.

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Authorities discovered Marquez was using a Facebook page “Good Vibez Only” to sell psychedelic mushrooms, marijuana, and THC products via mail.

Suffolk County District Attorney Timothy Sini says the page contained advertisements for an event to be held at Marquez’s Port Jefferson home on April 20th.

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“The defendant was going to sell drugs at this party, including marijuana, concentrated THC, edibles, and mushrooms,” Sini said in a statement. “It was called the ‘First Annual Good Vibes 420 Party,’ and I assure you it will be the last.”

State Police intended on raiding the party, but Sini says after receiving information that Marquez fed a pot brownie to her son they executed the search warrant ahead of schedule and placed her under arrest.

Her son was treated at a local hospital before being released to a relative.

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Marquez has been charged with two felony drug charges and three misdemeanors, including unlawfully dealing with a child.