Hi!
If you were my patient, I would advise you that if you are having regular periods you are probably ovulating and may not need to wean your daughter.
You could check ovulation predictors which are available at most drug stores, or you could ask your doctor to do a progesterone level to see if indicates you are ovulating. Your husband should do a semen analysis too, even though he has fathered one child (which is definitely a positive).
The elevated prolactin from breast feeding may be playing a negative role--ask your doctor's opinion about that too.
Good luck!
Dr B
Thanks for your response. I think I'll try the ovulation kit first then see if I still need to make an appt with my Dr.