Not all babies need the same amount of sleep.
It sounds like he is sleeping great at night. Is he happy during the day?
My DS2 has 3 naps during the day. The first 2 are 30-45 mins and the last 3 hrs. The 3 hr one he needs help resettling but I can tell he wants to be asleep because he cries and keeps his eyes shut/roots around and after a quick feed/rock is back to sleep. When he is ready to wake up he smiles and is happy so I get him up.
How long is he awake in between naps? At 6 weeks I'd guess he would be getting tired after about an hour to hour and a half.
You say you don't want to devote all day to putting him to sleep. Could yiu get a carrier? He can sleep while you play with your other LO.
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