There are currently no cheats or codes of any kind available for Virtual Families 3, there is also no indication from the developer whether they plan to implement a system in the game that will enable you to redeem codes to gain rewards such as items and coins. All that has been confirmed at the moment is the development of pets, more storyline, more items to buy at the store, and more events. So to reiterate, Cheats and Codes are not currently available in Virtual Families 3.
Although it is possible to hack some mobile games, it is recommended that you don't attempt to do so with Virtual Families 3 as the likelihood is that unless you have the right game hacker apps and know precisely what you are doing, you will mess up the game.
Take a look at our How to get Free Coins Guide to find out the different methods you can use to gain more coins in Virtual Families 3 without spending real money or using hacks.
Virtual Families 3 Mods Apart from looking for cheats, you may also be looking for modded versions of this game. There may still be some out there promising free coins, but generally you should keep clear of these as they won-t be from official sources, and may be packed with malware - really risky.