3 month old sleep

My baby girl turned 3 months on April 8th. She could easily sleep 8-9 hours through the night but at her 2 month apt the nurse said that’s way to long for her to sleep through the night. So I’ve been waking her up at the 6 hour mark to feed her & she goes right back to sleep. I hate waking her up bc she’s sleeping so good. She has slept through the night since 4 weeks old. She drinks 4 oz bottles every 2-3 hours during the day then her last one she has at like 11 Pm& she goes to bed for the night. Should I just let her sleep? Or what did you guys do? I’m going to ask at her 4 month apt.

My mom says never to wake a sleeping baby & she will tell me when she’s hungry & my dad says I should be waking her up to feed her like the nurse says.

She also sleeps in her own bed & is on a schedule.