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Congratulations on becoming a parent :)
I can understand
your concern is quite understandable
It is heartening to note that most of his vital functions are reported as normal,
It is likely that lymphatic drainage maybe a problem here
The good news is that this is likely to improve once he starts walking,
since the use of leg muscles will help 'push' the fluid out ....
So at present I would recommend watchful waiting, and further interventions only if the swelling fails to improve over the next few months
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