Hi my daughter is 3 weeks old and has developed lump like swelling on her left side chestwall.. it has increased in size over the week..we identified it when she was 2 weeks..she as a baby doing very well with no symptoms or pain in the area..she currently weighs 4.5kg on breastfeeding...we took USG as per our peadiatrician and were told the mass lesion lies at submuscular region and it's benign with no communication to nearby organs or tissues.. we were asked to observe it for another 3weeks... attaching the picture..pls suggest what it's and would it create any harm to the child ?