Please help

How do I help my 2 year old daughter adjust to having a baby brother now. She does okay when dad is home but when it’s just me, her and baby, she has melt downs. I even cuddle with her and baby or just her but she’s still struggling. I know it’s gonna take time and it’s only been a week but I want to help her feel better and not cry as much. She’s normally happy and never cries 😭