yes, it is as im only 15 and got it at the age of 13, its called juvenile arthuritis
Usually stiff sore or swollen joints are a pretty good indicator. However with forms of arthritis like Rheumatoid arthritis which is an Autoimmune disease other parts of the body may be effected.
i have not heard that arthritis can cause lupus but it is a common symptom of lupus. SLE causes are not yet know but is queried to be caused by genes, UV light and virul transmission, though i believe the latter may be triggers for the former.
Both men and women tend to shrink as they age, due to deterioration of the vertebrae and the discs between them, both of which cause shortening of the backbone. Also, women are somewhat more prone to osteoporosis, which accelerates the deterioration, and they tend to be shorter to begin with, making some older women seem especially tiny. well i think that it matter how they eat. Plus at a certain age the stop growning.
A broken bone in a toe, even though it is small, can still be splinted (or placed in a cast) like any other broken bone to immobilize it; then it will just heal by itself in about 6 weeks, normally.