EMPIRE OF THE SUN (1987) Jim sings 'Suo Gn'

#Welsh language lullaby Suo Gân in the Steven #Spielberg picture. It would be interesting to know how this made its way into the script as Bale was born and raised in Haverfordwest. Was this Spielberg asking him to recall something from childhood? Or was it pure coincidence that an actor from Welsh-speaking #Wales ends up singing it in a major US production?