constipation persistent

In the past, I have given her bioplasma which has a nat phos 3x in it, and there were no changes. I could try it again I suppose. Her diet is "ok" -- probably could use more green veggies, but this problem started in infancy. She was vaxed at birth with hepB and received immune globulin, too. Her first stool was OK but her second stool and subsequent stools had a terrible rancid odor to them. Very different than her brother, who was also breastfed like she was. His stools never smelled like that. She would only stool one time a week, too, not several times a day like I expected. THis continued up until around her 7 or 8 month shots and she received many in one day. Then her bowels seemed to stop working and her stool was building up in her rectum and no desire to pass it until it was very large, too large to pass. After that, I began to keep her regular using glycerin suppositories but periodically would find something that would cure it. But again, it would only last a few days, or at best about a week or so, and then she would seem slightly ill (warm to the touch, tired, not want to do anything) and then what worked for her never would work again. Once, pulsatilla 6x worked for her--she had a dose at about 10 a.m. and about 2 p.m. she had an urge and passed a normal looking stool...but it never worked again, and other doses of pulsatilla do not work.
Should I try the Nat Phos at the 6x by itself or do you think that if it was the right one, that it would have worked in the bioplasma at the 3x potency?

OK well then I shall certainly give it a try! I'll post back in a few weeks and let you know how it turned out. Thanks!