Question about ultra sounds

My aunt who is entrust to involved in social media stocks me ( the little that I post) and today I get a message that she is questioning how many ultra sounds I've had ( I've had three, one was elective) I'm almost 20 weeks pregnant and high risk because of my weight. She messages me telling me the acog only recommends 2 throughout the whole pregnancy and questioning the health of my child. My baby is 5 days bigger then he should be and in perfect health. So my question is how many ultra sound as is normal?