Email Statements with Associated Invoices?
Not that I know of.
But you might be able to duct tape something together using the Merge Reports and Merging Order fields on the Send Reports (SM205060) screen since basically what you want to do is merge multiple reports together. You'd have to modify the Invoice form to print all invoices for a certain statement.
Note that you have to click the SAVE TEMPLATE button on a report for it to show up in the Send Reports (SM205060) screen and, as far as I know, the parameters get baked into the template so you can't do any on-the-fly parameter editing in the Send Reports (SM205060) screen.