My 14 week old has been fighting bedtime for the last couple of weeks (since her 2nd lot of imms incidentally but that could just be coincidence). She naps without too much fuss during the day but bedtime takes at least an hour and a half to get her to go down and get into a deep sleep. After bath I BF her and she usually falls asleep in my arms. I try and rouse her slightly so she's not waking up somewhere different and that's the problem. She tends to sleep in her crib for 5-15 mins and then wakes up screaming. We then have another hour or so trying to resettle her until eventually she's exhausted and gives up, never before 8pm. I've tried making sure she's tired and making sure she's not overtired but it seems to make no difference. Even my normally endlessly patient DH was feeling the strain last night (we tend to take it in turns as neither of us can stand the screaming for too long!). It's not colic just seems to be fighting the sleep process and is outraged that we're trying to get her to sleep!! Previously I would have just put up with it but we have a 3yo who is being disturbed by the bedtime antics and is becoming a very tired boy 
Any advice or suggestions gratefully received!