Hi! I'm so glad you found this site too!

I was out with a friend yesterday who has a 3 year old, and a 3 month old. Her first was/is very high maintenance...he was exactly like you describe your son (crying if put down, lots of troubles sleeping, etc.). Now her second is SO laid back...she can lay him on the floor on his tummy and he'll stay like that for half an hour no problem. She says 'now I understand what it's like for other parents'!
You're right in that if your little one is very persistent (aka stubborn

) letting them cry is often not the solution. For instance, with my son, we didn't do CIO (cry it out) because I was convinced he would cry for 12 hours. Even now, he can't do time outs alone in his room. He will cry and scream and throw things. I think he gets scared being left alone like that. Worked great with my daughter. Every kids is so different!