FET next month with same 5BB embryo grade — could the gender be different?

Hi everyone, I’m having a Frozen Embryo Transfer next month. My first successful transfer was a day-5 5BB embryo and we had a baby boy. I have another day-5 5BB from the same cycle and will transfer it soon. In the UK we can’t do gender testing, so I’m curious: has anyone had two embryos with the same grade (like 5BB and 5BB) that led to different genders? Or did you find they were the same? Also, any FET tips (what helped you physically or mentally) would be appreciated. Thank you and good luck to everyone!