When my friend brings her to my house, she touches things she has been told not to touch, including my old dog. My friend is at her wits' end and so is the mother. She screams at the child and is ready to give up. Her parents only talk to her in Spanish, her grandma speaks both languages and I talk to her in English. There is definitely a problem, but not because this little girl is learning two languages.
Children do that all over the world and they can be managed just fine.
A young bilingual talker may jumble her words at first, but she's probably using three-word sentences, which puts her in the normal speech range, and she is talking well enough to be understood by her grandma, so it looks like she has a listening problem, not a speech problem. That's not surprising. At this age a child is much more interested in what she says than in what someone says to her. A child does notice, and responds miserably, to screams, angry words and constant admonishments, however, especially when they're dispensed by the people she loves best. This child will behave better if you lower your expectations, change your methods and make it easy for her to be good.