New to steam games, how do I use (purchase) 2 copies of Terraria to play on the same steam account with my kid?

[crimpshrine42]

I have a kid, 2 computers. My computer, his computer. I have installed steam client on both computers, logged into both computers. Bought 1 copy of terraria and installed on both. I can launch Terraria on his computer but when I go to launch it on my computer it says someone else is already playing that and will be logged out if I continue. I don't mind buying another copy, just want to make sure this will work. If I go to the terraria webpage in the store and add another copy to my cart and purchase, will the steam client be smart enough to let us both play at the same time?

Thanks for any help.

[cSg|mc-Hotsauce]

You can't. 1 account can not play on 2 PCs at 1 time.

Create a new account for your child, enable Family View for that account and purchase the game again on that account.

[JosXa]

In Terraria specifically, you can manually start `TerrariaServer.exe` on one computer, enable offline mode on both devices, then start the game (by using the dropdown "on this computer" item so you don't connect to the other session) and connect by IP.