Planned order for Collective requirement

I have parent material who is having child which is colloective material.

When I increases quantity for child item and do plant lavel Mrp then everytime new planned order is created . Iam expecting changes in existing planned order.

I had chosen planning mode in Mrp run screen as delete and recreate planning data.

Is there is any other config setting for this.

Also tell me how to creat to have default operation details in production order which is created with material or without material. Is there is any other config setting for this.??