grandma is angry over my baby's weight

Taylor.
I am 36 + 4 weeks today, and just had an ultrasound done. When I got home, my grandma was over and wanted to know how my appointment went. I told her the doctor said everything looked great, and that she was measuring at 6.3 lbs. She immediately got upset and said "that's a REALLY small baby" and "my smallest was 9.5 lbs" she's making me feel like I've done something wrong. Every baby in our family has been around 10 pounds. I'm literally starting to feel guilty, like I did something to make her smaller. I know the doctor said she is a perfectly normal weight, but I can't help but feel bad now. 😞