I have a 21 month old SWCAH son that we put his pills in applesauce or yogurt during the day when he is awake. We don’t even crush them for that.  When he gets his early morning dose I dissolve his cortef in a little bit of apple juice on a spoon.  We tried the water thing and he immediately spit it out.  Good luck.  We are also in the same boat as you with weight.  Connor still doesn’t weigh 20lbs. UGHHHH!

Good luck

Tammy