Will I lose iTunes purchased music when changing acct names?

My son and I both used one iTunes account to purchase songs and have a big library of music. He's moved away and now I want to have my own iTunes account (current account is in his name and username).

If I create a new account, will I lose the current library and/or the previously purchased music from my computer? If so, how do I prevent this from happening?

I want to make sure I take the right steps to keep my Library and purchased music.

Thanks for your help.