Tina has shown over the past year irritability as well as anger and lack of remorse for hurting her older sister. Tina also tends to be premeditated with the hurting of her sister when she is having tantrum outbursts as well. Tina also shows similar behavior at daycare that she attends 4-5 days a week. Tina has created a problematic dynamic at home with her parents very stressed and worried that the current behavior will not stop as she ages. What can Tina's parents do that would be most beneficial to her long term?