is this normal eating for a 7 week old baby?

Daycare teacher here, I'm wondering if my 7 week old daycare baby is eating like he normally should? He's with his grandma and she's not concerned about it, I'm curious because he barely ate this morning. He had 3 ounces until 2pm when he got there at 8am. He just kept refusing his food until the end of the day and then he acted like he was starving to death. I figure he'll eat when he's good and ready but still. He wasn't cranky or anything, he wanted to sleep instead of eat.