You can configure a threshold on your phone to be notified if the temperature raises above the limit.
The device keep reading your kid's temperature over the night, so you can have a good sleep.
Keep monitoring over the internet through your smartphone, even when you are away from home.
The ESP8266 keep posting on every 1 minute (to be configured) the temperature of your kid over the internet to the ThinkSpeak website.
The elastic arm band has a DS18B20 (temperature sensor) and must be placed on your kid's arm, in a way that the sensor stays toward the armpit.
So, you will need to install the android app (babyTherm, I'm still developing it).
ESP8266 - ESP03
DS18B20 - temperature sensor
Lipo battey 500mAh
Smartphone + app