i'm lumpy 
panniculitis. don't know if that's what you have or not. it (mine) is panniculitis lesions in the sub-cutaneous fat. i had a biopsy and it was dead fat cells and microabcesses. hard to kill a fat cell.... that's all the pathology report said, for that i gave a hunk of side meat, haha, think they'd have at least identified cells, or found lyme.
dr said it was erythema nodosum but it is not. i thought lupus profundus, but found an article on panniculitis and lyme a while back... i posted about it on here a LONG time ago, didn't get any answers.
not up to doing any searching for you, i am down with strep throat today, and will be busy catching up when i am better. but google it
may be what is going on with your girl.
for a while mine were TERRIBLY painful. my ND said the pathogen was hiding in the nerves, and when they came to the ends, my immune system 'saw' them and attacked. which is why those hurt so bad... they were at the nerve endings. made sense because it was the same timing as bells palsy, so it was definately in the central nervous system.
now "it" has kind of moved on from the nerves and they aren't so painful. if i do not get enough sleep, if i overdo it, if i spend the day in the sun... i can count on waking up with a dozen or even 30 new ones. when i am feeling good, getting lots of rest and eating right, and NO STRESS, i don't get any for a little while. problem is, when we feel good we tend to overdo (HA, has that definition ever changed for me!) then ---> lumpy again.
each lesion lasts anywhere from an hour to weeks. sometimes several just kind of 'grow together' and that HURTS. i have had them get 6" across by 2", raised about a half inch. as with most lyme symptoms, it goes in tides. really flares if i get a virus or injured, indicating to me, a screwy immune system at fault.
really wierd. one time i got a burn on my arm and immediately got several huge "lumps" around the burn. same if i get any little bump or sratch. once i was eating dinner at my sister's and her husband said "LOOK at her (my) arm!" we watched four nice lumps grow. 
i have had them on the outside of my thighs, my BUTTOCKS
my trunk, my arms, a few on my face even. usually they are not noticable by sight to others but can certainly be felt. sometimes they are big enough they are easy to see. when they were at the nerve endings, they bruised. now they usually don't.
usually now - the past 6 months or so (knock on wood) - they are not painful other than a few exceptions. and they are much smaller, like pea sized or half-walnut sized. smaller is good because it means less infection.
refered from dr to dr, they take pictures, shrug their shoulders and offer to send me to another. then for lack of knowledge, my gp diagnosed as erythema nodosum even tho it does not match other than being panniculitis lesions. then naturopath and state university hospital dr both said it was more likely lupus profundus. definately autoimmune.
if you find out how to treat it, let me know, haha (NOT really funny, is it?) i've been dealing with it for a year and a half.
sincerely............... Loribelle