wah!your son's name so Japanese

Mummy says; Zen wasn't a Japanese name.

1)Zen to mummy and daddy is a short form for Zenith which means at its peak or most successful or powerful.

2) Zen as in BUddhism ;
Zen is deeply rooted in both the scriptural teachings of the Buddha Siddhārtha Gautama and in Mahāyāna Buddhist thought and philosophy. What Zen emphasises is that the awakening taught by the Buddha came through his meditation practice, not from any words that he read or discovered, and so it is through meditation that others too may awaken to the same insights as the Buddha.

http://en.wikipedia.org/wiki/Zen#Zen_teachings_and_practices

mummy says; ZEN BUKAN NAMA GLAMOUR OK!!!! it is more of a religion insight which means awakening taught and also mummy hopes whatever Zen does is at his highest peak. Just do all his best.