My 21 month old has all of a sudden started to only want her dad. Finding this very difficult as he never really helped me until now unless it suits him. She has had really bad reflux from birth and so has always been a very bad sleeper so I’ve had my hands full for nearly two years. All of a sudden she has been only interested in her dad and I’m struggling to deal with this. He’s acting very smug and enjoying every minute of my struggle. Help!