As you said - velcro. Which is very cool, but man it can get crazy sometimes. Like when they stick their head in the shower, then you have to laugh when hey get a face full of water and get that look.
Has something happened in the backyard to scare her? Any wildlife?
Without being home when she gets on the bed, you can't redirect or correct it. Close the door to avoid it. Same with the trash. If you aren't there to correct, put the can in the pantry, closet; just where she can't get to it.
I am concerned about the snarling and getting in between anyone and the kids. If there isn't a threat, it would be appropriate to be watchful, but not snarling.
I am also concerned about what you describe as moan growls at the 2 year old. What is happening when this occurs? Is it random? Is the 2 yr old being a typical 2 yr old and curious yet just not quite sure how to interact with a dog yet? Definitely get a trainer involved in this to get eyes on what is happening. Monitor ALL interaction between the baby and dog. Family Paws-New parent classes dog and baby
can give you some ideas and also provide a list of trainers.