Kiley had to be flown to Cook Children's hospital in Fort Worth, Texas. The hospital sees between 17 and 25 children bitten by snakes every year.
The bite caused Kiley's finger, hand and arm to swell. Her finger also turned black, Kiley's father Michael Cook told WFAA.
The day care's owner told WFAA that employees would examine the playground for snakes before the accident.
Nataly Horn said she looked at the playground earlier that morning when she took her class outside to play.
Additional safety measures will be taken, including adding mesh fencing to the property and having experts come take a look at the surroundings, giving advice on what can be done.
The day care has been in business for 18 years.