DS1 was great until 10 months, then would not keep on from 10 months until 25 months then suddenly became obsessed with 1 particular hat and is now great at keeping it on.

When he wouldn't I would put it back on a million times or tell him we would go home if he didnt keep it on, 1 warning them home OR put in pram with UV cover on.

I now have same issue with DS2 grrrrrrrrrr dam age thing!!

Good luck