By Alexis Tereszcuk - Radar Entertainment Editor
According to an eyewitness at the party in Chattanooga, Tenn., held on July 3 at Maci's aunt's house, the underage reality star was boozing it up!
"I saw her drink a lot," the eyewitness said. "She had at least 6 beers and she was at the party for four or five hours."
When someone asked the MTV star why she was drinking alcohol, she giggled and said "I'm almost 21."
Maci was at the party with her parents and her young son Bentley, but according to the party-goer, "the more she drank the less attention she paid to her son. Her parents were there taking care of Bentley and her."
Luckily Maci wasn't driving, but she definitely seemed drunk the source said.
"If you said boo to her she would laugh. She was rambling about her TV show, saying that she didn't make a lot of money there but that she has a lot of other opportunities now."
Maci turns 21 on August 10.
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