What kind of time out do you give her,what happens prior to the episodes of kicking and yelling sounds like something is upsetting her, how is she at school does she do the same there, what does her Teacher think. Get her Dad involved morewith games and outside activities and one to one attention for her, ,as there is a younger sibling she could be feeling left out, focus on her positive side and praise her when you find her doing something right.