Guilt—Olders and newborns

I feel awful about the fact that I just can’t get over the anger and aggravation I feel towards my 5 year old right now. Our newborn is so relaxed and calm and it’s blissful. But our 5 year old is special needs and I just can’t handle it. It’s pissing me off and that makes me feel guilty because I love her so much too but she’s making me so mad….

**I’d love some advice on what I can do. I don’t want to develop favorites and I love both my children so much.