First Ultrasound- twins a week apart

I had my first ultrasound this past Monday for my rainbow baby 🌈 and found out I’m having twins! Which I was very excited about until the technician let me know that the one is a week behind the other.

One was measuring 7w3d heart beat 126

The other is measuring 6w3d heart beat 90

I’m wondering if anyone else has experienced this and what the outcome was. I know it can probably go either way for my second baby but just praying they keep growing.

Thanks guys!