I think you are being irresponsible, giving a mains operated lamp to a 5 year old child,
You have not thought this through, lamp from America, 120 v lamp, switch may not be of correct rating for use over here, suitable sized lamp may get too hot, yackety yackety yackety, in short it is probably not designed for use in a european country. you still have time, bin the thing, and buy a decent responsible present
lamps are NOT toys. you give toys to children not mains operated lamps.
I can see the head lines now:
Irresponsible parent buys child U.S.A. Light, child electrocuted, now all shook up