Approximately how long should I give them to see if they will bond? They did simmer down last night, no more frisky business. And they seem to be socializing more and more. I took out their house because it only fit two pigs so one would always be left out and put in a blanket that way they could all sleep together and they did. Is this a good sign?
I have an extra large cage and it does have the option to divide it into two, I just don’t know if I’m ready to take on another Guinea so soon
I feel like I really messed up
How old are they all?
How big is their cage?
Did you introduce them on neutral territory?
How long have they been together?
The chances of them sorting out a functioning hierarchy and staying that way for the long term are very low sadly. 90% of boar trios have to split up at some point. Its a rather unstable grouping and unfortunately it can go wrong at any moment. You can certainly choose to leave them together and see how things go but you need to keep a very close eye on the situation. If there is any sign of bullying, tension etc, then you do risk fights occurring.
You also need to be prepared for the risk that may also come to your original pair. If you separate now, you will hopefully be able to keep the original pairs relationship in tact. If full fights do occur, then there is a risk they may also fall out so all three will need to be kept single.
The new five month old piggy is just at the start of his teens so you are going to see a lot of hormonal behaviour from him for many months.
Any cage which needs to be divided into two - each side needs to meet size requirements for the number of piggies it is going to hold.
Two boars together need a cage of 180x60cm.
One single boar needs a minimum of 120x60cm.
The cage for the three of them to live in together needs to be three square metres/32 square feet - so a 300x100cm cage. This is to ensure enough territory and space each. It won’t make them get on, but lack of space will cause problems.
Regarding taking the house out. if you’ve taken the hide out and they have nowhere else to go, then it’s not necessarily a good sign that they all went on the blanket. They simply had nowhere else to go, not that they are going to be compatible.
You need to make sure you have three hides in the cage and that each hide has two doors (any single exit hides can cause problems if one piggy traps another inside it). You need as many items in the cage as you have piggies - so three hay piles, three bottles, three houses.
I'm not sure this will settle down, and you don't want things to turn aggressive. Even 3 boys that have lived together from birth have a solid chance of falling out at some point - that's how I got my lovely George (on the left here). If people have had to split boars a good way is to have two neighbouring enclosures split by grids so the boys can see and smell each other through the bars. However it's always better to have a happy pair and as much as your youngest boy is disrupting right now he can't help it... it would be a shame if he was alone in a permanent 'time out'.
Good luck with your boar adventure! 
