My LO normally gets up once a night to eat and sleeps about 4-5 hours before that feeding and about 4 following. He’s usually up for the morning around 7. Last night he slept 8 hours straight without waking, ate 5 oz. and went back to sleep for two more hours. I just checked in with my mom who watches him and he fell back asleep at her house around 8:30 and is still asleep now over an hour later. This is not the norm for him - should I be concerned?