When should I get an US?

Macy • 24. Married. 2 little boys. Here we go again! Prego with baby #3! Praying for a girl! (Literally) 🙏🏻
One of my family member works at a hospital as an ultrasound tech, and she can scan me as a volunteer whenever I want. I found out I was having a boy at 12.5 with my last pregnancy. So should I go in at 12.5 weeks again, or wait until 13 or 14 weeks? I'm so anxious! 😝😝😝