will be traveling to Beijing in February with my 2 year old son, will it be to cold for him?

It may be cold for your son when you are outside for traveling. The average temperature is around -4 to 6C during the Feb, but it may not snow a lot in that month.
If you plan to take your son to come to China, it is suggested to prepare down jacket and thick sweaters for him. In the rooms, please do not worry about the temperature, because the heaters are very cool.