If you plan to take your child to the doctor's office, beware of what you feed him or her for breakfast. They may see this and decide that a call to DCFS is in order:
Thanks to my son's affection of climbing stairs and being naked, I noticed this frightening (and rather large) mark on his thigh before anybody else did. After much panic I thankfully noticed a tiny purple spot on his diaper as well. How I missed the stray (squashed) blueberry in his high chair when I cleaned up his breakfast is beyond me. Thankfully it was nothing a little soap couldn't take care of! Crisis averted.