Answer: It's amazing that babies can compartmentalize their different caregivers. Sleeping great at daycare and terribly at home. Part of it is likely that he misses you and doesn't want to waste time napping when he could be with you. Part of it is likely that the lack of nighttime sleep success is effecting your nap success. Keep offering the naps and work on night skills. If you have solid night skills, you could do weekend nap coaching. 4 months is typically when major sleep changes occur and sleep skills need to be learned. Solid night sleep is the building block for solid nap skills so I would look very carefully at the nights first.
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