I think you should read 'siblings without rivalry' - your local LLL group will have it in their library or the normal library should have it. Also Liberated Parents, Liberated Children and How to Talk so Children will Listen and Listen so children will talk - I really think these books will help you in your situation. It's really hard I know, it's frustration of not being able to express themselves vocally - have you tried Baby Sign Language the book Baby Signs is great - it could really help also if you've tried Toddler Yoga it can also work miracles - I do yoga with my kids and it really helps dd is 4.5 and ds is 19 months.