Samantha Andersen said she noticed some of the gummies in the bottle of Zarbee's Natural Vitamins were clumped up together.
When she placed them on a plate to separate them, Andersen said she noticed tiny metal shavings in the gummies.
She says she has been feeding the gummies to her toddlers for months.
"I feed these to her," Andersen said. "I feel like I have failed. I feel terrible that this metal is in her stomach."
Andersen's 3-year-old daughter was taken to the emergency room, where pieces of metal were found in her intestine.
The FDA is investigating the complaint.
Zarbee's has not commented on the matter.