Bluetooth is not dangerous for a child's health as the transmission power of the radio waves is too low to cause any harm.
Various scientific studies have shown that this technology has no effect on people's health.

To give evidence to this statement, we must consider the maximum threshold of SAR values imposed by the European Union (SAR = "specific absorption rate", which indicates the percentage of electromagnetic energy that is absorbed by the human body when exposed to a radio frequency electromagnetic field).

The European Union has set a maximum level of SAR values equal to or lower than 2 W/kg. For example, the average values of headphones and bluetooth headsets have an intensity of between 0.001 and 0.026 W/kg.

Tata Pad has a SAR value of 0.0099 W/kg, which is 200 times lower than that limit.
For further information, we recommend reading the following articles: