well i live with my parents, so my son spends time with my parents everyday. As far as leaving him here while i go out, rarely happens, unless i'm just running to the store real quick. Havent had a date night in almost a year. My "in laws" see him a few times a month, but have never had him over night, although i think we might start letting them have him over night once in a while, since they really want him there, and he loves being there so much. He's only spent the night once without me with him, and that was with my sister about 4 years ago.
My sister (who has 4 kids, 3 of which are under 2) brings down 3 of her kids (the ones under 2) down to my parents the first weekend of every month so she can have "a break" with her husband. But her mother in law lives closer and she drops the kids there every other day.