It sounds as if when he was sick he got out of routine, maybe he went into your bed? and got some drinks maybe a snack or two, and he likes that ,so you have to let him alone in his own crib when he wakes up, once it isnt doing anything for him he will give up.Did I understand you that he went to bed around 11-12 at night ,Thats too late for a 1year old 8pm is a good time , he sounds like he is napping a lot during the day maybe he doesnt need that much, so cut the afternoon one back, no wonder you have had him up till 11-12 at night if he sleeps during the day till 4pm.So get a good routine going , thats the problem he hasnt got one .Good Luck