Happyness: He, like mother void, came before everything and, unlike mother void, who refused to stay in void happiness, he decided to plant one of the trees in the multiverse, which this road tree THE MULTIVERSE FROM MADNESS COMBAT

As for sadness, he gave up planting his multiverse tree because it was stepped on by happyness as a brother's joke

On a random day they meet Zardy and since Zardy didn't know that they were practically his uncles he made a pact with them and so happiness and sadness.

So they stayed in the corner of Zardy's head where everyone he made a pact with is located.

Then zardy went to mother void and she managed to realize that zardy had made a pact with happiness and sadness (Well it must be because it had TWO FLYING HEADS, ONE WHITE AND HAPPY AND THE OTHER BLACK AND SAD).

Mother Void was obviously furious with Zardy for locking his uncles in her head but then Happyness:

"Don't worry my sister, the part of your child's mind that we are has games to entertain us. In other words, there's no problem"

Mother Void was reluctant for a few days about this because HER SON LITERALLY MADE A PACT WITH HIS UNCLES AND NOW THEY STAYED IN HIS MIND PLAYING UNO

Now the powers

The powers of happyness are:

• All madness powers from madness combat (In other words UNLIMITED POWER)

• Make someone crazy whenever you want

• Control the people he drove crazy like a puppet

• And finally, evoke weapons like swords, bazookas, mini guns and others

The powers of sadness are:

• Making people depressed and controlling them like puppets

• Summon snakes in place of his jester's hat

• And cry flammable, poisonous black goo