Simon Wilkerson, 7, knows why he likes soda.
"Because it's, it's delicious," he said.
His 6-year-old brother, Milo, also enjoys the occasional soft drink.
"Because it's yummy," Milo said.
And sometimes their 2-year-old brother, Jude, takes a sip of soda, too.
But a new study from Columbia University shows all that soda may affect the behavior of young kids.
"Children who are consuming four drinks of soda are exhibiting higher, higher aggressive behavior, attention problems and withdrawal behaviors," said Dr. Shakira Suglia, the author of the study.
The study looked at data on nearly 3,000 5-year-olds and found 4 percent drank four or more sodas a day. And 43 percent of children in the study drank at least one soda a day. Researchers found even that amount could make kids more aggressive.
"As the number of sodas increased, so does the aggressive behavior," Suglia said.
The American Beverage Association disputes the findings, calling it a "leap" to suggest soda causes behavioral issues.
Elisabeth Wilkerson says she limits how much soda she lets her boys drink.
"I think as long as you balance it with healthy drinks and healthy foods and activity, once in a while isn't going to kill them. And it removes the taboo," she said.
Doctors say it's a good idea to limit soda because sugary drinks have been linked to other health problems, like obesity.
The study's researcher says ingredients in soda, like sugar and caffeine, may affect behavior, but more study is needed.