What does block explores say?
If you see a transaction from the address owned by your son to an address owned by you, it means that the transaction has been made.

A solution for you is to export your private key(s) from Armory and import it into a SPV wallet like electrum.
In SPV wallets, you don't have to download the blockchain and you won't have such troubles.

Take note that if you use a SPV wallet and you don't want to download the blockchain, you have to connect to servers provides by third parties and that may harm your privacy.