Evil sims have to have a low enough relationship with another Sim. I should have added that Jared Frio's daughter also exhibited the Evil Trait, which is why he was getting along well with his daughter. Evil and Mean-Spirited Sims actually get along quite well with each other, unless the mean-spirited Sim is also a good Sim. Evil Sims can still have polite conversations, and exhibit the friendly trait, just like mean-spirited Sims can still donate money to charity and want to congratulate others on their wedding day, when they have the good trait.
I noticed that Grumpy Sims autonomously flip-flop between negative and positive interactions, with no neutral balance. One of my grumpy sims was autonomously politely having a friendly conversation with one of the Roomies. When the Sim got really tired, the conversation did a complete 180, and the Sim just started arguing, and fighting with that same person. When everything is fine and dandy and their needs are met, they have autonomously polite conversations, however, any sort of negative influence on the Sim, (such as low needs, crying babies, another Sim's rude remarks), they will autonomously rudely interact with other Sims, especially the parent of the crying baby. This happened when Gunther Goth was sitting on the table minding his own business, trying to get work done, at Central Park. Marty Keaton's toddler son was in dire need of a nap, and was very cranky. As soon as Marty Keaton put his son down, Gunther, immediately yelled at him, simply because it was Marty's crying baby, and it was getting on his nerves. Grumpy Sims might be the most difficult Sims to please. Hot Headed Sims, have actually gone into rage, and even broke a few objects on many occasions. Justine Keaton actually broke a dollhouse, when the Repoman took her belongings, (she forgot to pay the bills), and had a broken sink, flooded kitchen, from the broken sink, a crying baby, and was extremely tired to top it all off. Claire Ursine broke her TV, after her ex-boyfriend, had autonomously yelled at her, when I was playing with her ex-boyfriend Jared Frio (his wishes both stated, "Be Mean To Claire" and "Snuggle Candace"), and had him visit his daughter. So after I did my "testingcheatsenabled true" and fulfilled his wish to be mean to Claire. Claire broke the TV. Tamara Donnor broke a chair after being rejected by Cycl0n3 Sw0rd, being very hungry and very tired, getting creeped out by Stiles McGraw, and having her stuff repossessed when she forgot to pay the bills. Xander Clavell broke the stereo a few times too.