Basically I was getting ready to take my first town and I was Rank 4 so I could make 3 parties other than my main. I created those armies and gave command to my brothers and sister but when I went to war I was unable to give them commands to follow me or do anything useful really. I tried taking a castle expecting them to show up but because they kind of just wander around doing what they want I had to retreat when overwhelming numbers came to relieve the siege.