4 year old trying to hurt her baby brother

[flingaling77]

I hope someone will have some advice. My 11 month old boy is sometimes really demanding and whingy. He is particularly so at the moment due to teething. My daughter tries to push him over repeatedly and I can't trust her with him. I'm finding it really hard. Whenever my boy is demanding ( he can scream almost constantly at times) my daughter really plays up. I feel like I have nothing more to give. I would rather be at work than have them both at the moment. Feel ashamed to say but not enjoying motherhood much at the moment. Any advice or just to know I'm not alone would be good. Thanks x