My older son slept through the night when he was around 6 months old. On the other hand, my younger son did not sleep through the night until he was 3 years old. And even then, it was not every night. When he could talk he would tell us, My bed done! This was usually at 2 or 3 in the morning. Now younger DS is 16 and can sleep until 10 or 11 in the morning if we let him!

Aren't they smart so young!!

to do that. I could never let my kids cry it out, breaks my heart, but do find it tempting--especially with DS2 (but it might cause a trip to the hospital).