so why do you do it? He will just learn to stress about your return.

Crate training might be difficult at his age after having the run of the house, it works best from puppy-hood.

7 hours is a long time on his own, does he have toys that he likes ?
Perhaps a kong with food inside it.

What happens if you leave your bedroom door open?

I've been told some dogs like a radio left on when their alone for a long time, you could try that.

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