First of all, thanks to everyone for the input.
Second,
I'm the husband.
We've addressed the problem in the short term by taking Max (and Truman) to puppy camp for a couple of days so we can get settled with the baby without the added pressure of trying to fend off an upset Yorkie. They'll be back in a couple of days, though, and I'll be sure to incorporate these suggestions when they return.
I do feel like it's more intense curiosity rather than actual aggression, but Max likes to use his paws, and I'm afraid he could hurt her without even meaning to.
Thanks!