Hi Laura,
I am sorry that you are experiencing that with your sweetie, Delilah.
It must be upsetting for you.
I know one book that is sometimes recommended here is "Mine" by Jean Donaldson. I haven't read it yet, but it is supposed to cover issues such as resource guarding. If that is determined to be the case, by the more knowledgable members here. I know you'll get some great advice here.
I know was I a little hard headed when you first signed up, about the whole "Maltese & young kids" scenario. And I do sincerely apologize if I hurt your feelings, that wasn't my intention. Some breeds are just "easier" with kids than others.
But I know you are very dedicated and have a lot of resources at your hands. So I do hope the best for you, Delilah & your family.
Maybe with the right trainer, you can nip this in the bud, and everything can work out okay. I am wishing the best for you.