2 Ipods 1 computer alot of music and confusion.......

My stepdaughter and I both have a Ipod touch, our Apple ID's are different, as she got hers first. When she signs on to her account in Itunes she can see all her music that was originally on her Ipod (we recently got a new computer) and everything that came from my Ipod and my MP3 Player and everything from her Ipod shows a cloud beside it. When I sign in under my account name, I can see everything that came from my Ipod and my MP3 Player but nothing from hers and nothing of mine shows a cloud by it. Regardless everything that is showing in my ITunes panel I was able to sync to my Ipod including everything that came from my MP3 player. Even though my stepdaugher can see all the music the only thing that will sync to her IPod is the songs that originally came from it. Are we not able to share music if it was legally purchased from Itunes? I used ITunes match to make everything from my MP3 player legit.