Cole drowned July 1 while swimming with friends in the river.
His sister said he was struggling when he went under water and never came back up. She says his two friends went in after him but they couldn't find him.
Dozens showed up at the service to pay their respects. The group shared a lot of tears and laughs while remembering the good times.
Cole was known for being talkative, funny and kind.
He lost his mom to complications from Lupus at 13 years old.
His family urges everyone to stay out of the Sacramento River and to use a life jacket if you do go in.