Kim White-McClure, the boy's grandmother told 9NEWS her grandson's name is Bram Venn.
Several storefront employees were around when the accident happened.
"The mom was just holding her baby on the ground until the paramedics arrived. The anguish of the poor mom and the screaming of the woman that hit him," Allison Orchard said.
Emergency crews rushed to the scene and worked fast to try and save the toddler, but he was pronounced dead at the hospital.
Littleton police don't know how the boy was hit, but say the investigation is still active and they hope to have more information on Monday. As of Saturday evening, no arrests were made.
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