Yes it can be an issue, but all you can do is to continue looking for work. Being a mother w/ child is certainly a consideration (i.e. if you were a man, that one year gap will be an even bigger issue), but the unfortunate truth is you're competing against others in similar circumstances who are fortunate to be employed (or others who don't have the same life circumstances as you do but have stronger resumes nonetheless).
Again, all you can do is to continue job searching, do the best you can on the b-school applications, and hope for the best.
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