Any good ways to slowly stop my LO (now 22 months) from sucking his thumb? He usually will suck his thumb to sleep or for comfort (when crying ). If he is engaged in activities , he usually won't suck his thumb. But I want him to stop sucking his thumb completely

Try explaining to him why he shouldn’t suck his thumb and encourage him to try not to do it by planning some sort of reward system? Like he gets a sticker etc if he didn’t do it for the night. You may also consider getting a thumb guard to help him kick the habit! Good luck!