Hi and welcome.
Please attach a picture here s that i can give you better advice.
Thanks for the reply.
This looks like a congenital melanocytic nevus or a cafe au lait macule.
Both are possible causes and both darken with age and usually lighter at birth. In case of a Congenital Melanocytic Nevus, they are usually much darker even at birth but lighter variants are also there.
The final diagnosis will be made when the dermatologist examines it but both the lesions are nothing to worry about much.
Laser treatment can take care of both. And the chances of spreading are also not there.
Hope this helps.
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