Suggestions for handling a single lead with multiple email addresses?

Suggestions for handling a single lead with multiple email addresses?

I'm not sure what the best method is to handle a lead with multiple email addresses. Does anyone have a best practice tip? For example, I have a lead that I'm emailing and I use the BCC function. Once the lead gets converted to an account, often times they email me from a different email address. So, when I use the bcc function, it creates another lead instead of adding it to the correct account.

Any suggestions on how to handle this?

Thanks,

Brian