Reasonable?

At my job it's me and 2 other girls that run the front desk on different day's. My manager works with my 2 coworkers schedules all the time. I am the one that gets meshed around their schedules. I am happy with that, but do you think it's reasonable to ask my manager to work with to help me get a consistent amount of hours every week or pay period? I need it so I can start having a set budget to make sure I can pay for things every month. I do a lot for them and cover shift's and stuff all the time and I just really need a certain amount of hour's so I know I can have enough money to help my husband with bills and stuff. I know she may so no, but is it reasonable to ask?