Please recomend a mod for my son. No mobs.

My 3.5 years old son loves Terraria! He likes to dig, build stuff, explore... He just can not handle monsters. Could anyone please recommend a mod to me that would disable mobs spawning? Thank you.

P.S. I hope I post this thread in the right place.

No, there are no mods to disable mobs spawning as far as i know, thats just gamebreaking :/

Possibly, you could set up a server, (A private server, so it's just him) and download the T-Shock server software, then use a command to change mob spawn limit to 0? (This wouldn't prevent boss battles, but as he's young I doubt he will fight them in the first place.)
That's all the help I can give.

Maybe a "safe" map could be an option? I've never downloaded any maps before, so maybe I get the concept of maps incorrectly...

The only way to make a "Safe" map would be to download T-edit, or have someone get it for you, and make the walls of the world Glass wall, so he can see through it, as walls are the only way to stop spawns.
Although you would have to explain to him that he needs to destroy the glass walls to place his own walls, such as to build houses.
Turns out I CAN give more help.

No that wouldn't work at all.
First you would lag the world terrible.
Second mobs spawn anyway if your 'room' is too large, and that won't stop EoC from ruining the day either.

The closest I can think of would be buildaria, as it can set all mobs to nulls.
Unfortunately its other features are most likely a little overboard for what you are looking for...
In theory you could strip down the source code just to include that one feature.... Actually I've done similar before.

I've tried setting a mobs Max Hp to 0 with tconfig before and it effectively removes them from play.
So if you want to go through the trouble of making all hostile mobs max hp 0 with tconfig then you could do that.

Ah, never mind that idea then.
All you can do is make a server and set spawns off, as far as I know.

If you download T-Shock, register an admin account, and start a server with it then all you have to do is type these three things:
/login (username) (password)
/maxspawns 0
/butcher

logging in, well lets you type these other things. maxspawns o makes it for no other monsters to spawn. lastly, butcher kills all the mobs in the world that have already spawned. your lft with a "peaceful" world.

Already covered that.

Any way to automate that process?
It'd be handy if the 3.5yr old / parent doesn't have to bother typing all that in every time.

Nope, it isn't automatic unless your a coder...

Just a suggestion...
Let your son use a character with full hallow with full warding accessory and let him play on easy mode world.
Problem solve no mob can kill him...
and if he know how to swing a sword,, give him exca.

Why not just use TerrariViewer to edit in the best items on to your sons character, edit his health to max (Or infinite/rediculously high) full Hallowed armour with Obsidian Shield, Angel/Demon wings, dual hook (Or Ivy Whip), All accecories at Warding, and a Legendary Excalibur. Because if he's just going to be building and such, he wont be fighting any Hardmode enemies, and while in full Hallowed, he could just point, click, bam the enemies are dead. Infact, he'd have so much health and defence, he wouldn't even notice the mobs feeble attempts to harm him as they plink at his armour.
Just a thought, far less complex then stripping down the source codes and what not.

Edit:

Damn it, beat me to the punch.

I would go with server to control mob spawns

why isnt anyone questioning the whole thing? a 3.5 y.o. playing terraria?!?!
thats the age my brother started typing his first lines on the computer... just how weird is the world becoming?
anyways the only ways of how to create a peaceful mobless world are already named.. tshock, or the mods
but i dont recommend tshock since it isnt for 1.1.2 as far as i know since the devs want to see loads of money for somethi-.... i shut up before this becomes a spam thread <.<

I was clocking commander keen at that age /shrugs

that's the age i was playing lego with friends or was playing together with my two bigger sisters, I am always amazed (s/amazed/terrified) how soon ppl let their kids have contact with gaming software

This is the best and easiest way to set it up;

You start a multiplayer server for him and change its default spawnrate and maxspawns so that monsters won't spawn.

Step 1:
Download Tshock : https://github.com/TShock/TShock/downloads

Step 2:
Extract the download and open the folder
Inside the "Tshock 3.8" folder there should be a "tshock" folder, open that

Step 3:
Open the config.json file with notepad (right click > Open as)

Step 4:
In there you will find a bunch of things, but in the top of the note, you should see these two lines:

"DefaultMaximumSpawns": 5,
"DefaultSpawnRate": 600,

Change those to this and then save the new change:

"DefaultMaximumSpawns": 0,
"DefaultSpawnRate": 999999,

Step 5:
Start the TerrariaServer.exe, a retro-like command window should pop up, in there you will chose your world (and use the standard port 7777)

Step 6:
Start your normal Terraria game and choose Multiplayer > Join > Pick a character > The write the internal IP: 127.0.1.0

Ok, now you've got it all set up so that you every time have to run Terrariaserver.exe and pick world/port and then start the normal game.
The server IP is saved from last time you entered.

(To save your world you write save in the command window or exit, which will save and then turn off the Terrariaserver.exe)

Thats pretty much impossible, it would not only take a big element off the game but would also be hard to pull off.
Terraria was never meant for kids :|

So having endgame items doesn't solve the problem??, but I think this is the easiest way with out altering the game..NO??