J.S.
i'm 24 with my 3rd on the way married 6 yrs and work as a nurse 2 days a week. you will adapt and learn to balance everything. make sure you give your 4 yr. old a lot of attention esp. when the baby comes. try having some time for just the two of you if you can get you boyfriend to watch the baby or just play with her alone with the baby naps. but also, you must make a little time for yourself in order to be the best mom you can be. for now, take care of yourself, and just plan small things with your daughter. if you know you're doing your best, you shouldn't feel like you're neglecting her. good luck.