Is a 6.5 hour long sleep a lot for a 6 week old?

Emma

My 6 week old baby slept for 6.5 hours last night, the longest he’s ever slept. Usually he goes only 2-4 hours between waking up/eating. We told my mom this & she said he should be sleeping 6.5+ hours by this point anyway so it’s not a surprise. Is she right? I feel like 6.5 hours is crazy long for a 6 week old baby. The books I’ve read say they wake up 3-4 hours.