The big one taught him how to keep up with the Jones. The little one taught him a more valuable lesson. Also, there is a possibility of the new phone being stolen by jealous classmates. Both brothers do not earn any income. Yet the smaller brother, at 12 years old, knows the value of thrift.
Nobody can teach thrift in an era of consumerism and materialism.
Dad was happy that one son had not needed to keep up with the Jones. Big brother will splash on Ferraris but the small brother will have the inner strength to look after his wealth and not be a material boy. All dads live in eternal hope that their children will not be spendthrift. In 3 generations, the Chinese tycoon wealth is said to be squandered. Dad is not a tycoon, but the smaller boy has the qualities of one, Dad hopes eternally, like all fathers do.