Petty??

So my "mother in law" ...I'm not sure how to take her at times, but my SO has told me she is very two faced. Well I posted a picture of our baby her grandaughter and she commented and I said she is photogenic well she said "just like her daddy". I probably shouldn't be so upset about her comment but ughhh! I feel like she said that to piss me off...like why not "like her parents". Am I being petty about this??