How often are you feeding her? If it's every 7 days, I'd bump her up to every 5 days.. But reguardless, she's still pretty skinny even for feeding her once a week. Have you taken both of your BP's to the vet to get fecals done? I remember you describing in your other thread about your male how there seemed to be tunnels in his feces. I'm not 100% positive, but this sounds like internal parasites to me. It's possible for parasites to transfer from one animal to another if you don't wash hands in between handling and if they were housed in the same cage/their cages are close together or in the same room ( which is why it's always a good thing to quarantine in a completely seperate room). I would definately get them BOTH checked out by a vet though.

Also, if you were to feed her two mice, I would go with feeding her two of a size smaller than what you are feeding her now (which would be two hoppers from what I have read, correct?).