Shan with regards to the milk issue, with Zander's bowel problems (toddler diahorrea) we have had him checked out & there is no issue with milk or lactose at all so that's definitely not it.

Melanie, he's had nights with my parents before & it's never made a difference at all, he wakes the same with them as with me, but will accept Granma in the middle of the night.

Co-sleeping is definitely out as well, he thinks my bed is for playtime! He has his day sleeps there & sleeps much better as the room is darker, but as soon as anyone is in bed with him that's it it's playtime.

We have music, night light, sleep spray, we have cuddles in his bed every night so my smell is in his bed I would think, he has a dummy but isn't fussed in the middle of the night for it. There's just no room in our room to fit in a mattress, so that's not really an option unfortunately. He goes to sleep well & only starts up from an hour after we've gone to bed & the house is quiet, whether it's 9pm or 1am, just once we've gone to bed.