My baby is having a swellen red spot on her left ear. It is there on her at 4mnth after her birth. She is now 1yr old. It is spreading slowly.

May be birthmark. There are some "birthmarks" that emerge in the first few months on the skin surface.A common one is composed of a jumbled collection of capillaries that grow faster than the kid until about a year then slow to gradually shrink down by the 4-5th birthday.These are blood red, just under the skin & can have a stain quality or be rough.Your doc can tell you foor sure.