Gave my daughter my Ipod touch. How to get purchased apps

My daughter's ipod touch 4 broke. So, I have giving her mine since I have the Ipod phone. How do I get the apps I purchased for her onto this Ipod touch? When I try to drag the app from the library it gives me a red x. I'm logged in as the name I used to purchase her apps. However, this ipod touch I used my personal email address and had purchased my own music/apps. But, I deleted everything off the ipod touch. I'm trying to set up this ipod now as my daughters.