MFM referral in 3rd trimester

I’m 35+4 with di/di boys and baby B has consistently measured a little bigger than A. There has been a 3-5% difference in their weight until today. They had a hard time getting good pictures because they are so squished, but the measurements they did get showed A now measuring 6.8lbs and B measuring 5.11 lbs. just last week A was 5.6 and B was 5.8. My dr is referring me to a MFM because the difference is now 12%. Has anyone had this happen or gotten different results at the MFM? I’m worried they’re gonna want to take them ASAP if they get the same measurements.