Two xbox one game

You should be able to play it too. Did you set his profile as your home Xbox? And vice and versa. Sounds like you did it only one way. The silver account can share games too. I just bought MCC and my gf is able to play it. I play on her gold.

You need to install/download all games on your home xbox one account. If u purchased while signed in on your sons acc. I think that game may be Liscenced to him. If he doesn't have a home gold box, (i.e., his own paid account not under yours) then u won't
be able to use on both consoles. Just remember to buy all digital games on YOUR home xbox under YOUR home gold account...then you can sign in using your home gold acc. on any xbox and play...and any one can sign in on your home xbox and use your games.

UPDATE!

So i got this to work brilliantly, but now I have run into a problem:

I got the digital download of AC unity, but I put it under my sons account on my home xbox and I can't seem to play on the other xbox, can i transfew ownership to my other account the MAIN account holder?

Me and the missus do this as well. It's great when it's a game we both wanna play.

One thing I 4got, and it's very important...sharing ur games like this only works if u originally bought the game in digital form. I.e. From the xbox or MS store to download. Disc based games won't work for this...as ull need a disc for each box u have.
With digital downloads, they transfer from one box to another...