Our 2 yr. old girl is also on 10 mg/day. She gets half,quarter quarter. I just split it with my fingernails. I don't always get it exact, but hydrocortisone is a fairly long lasting form of cortisol, so every day she gets EXACTLY 10 mg, which is what she needs. This med. isn't like insulin, they look at it long term, not minute to minute. Also, for at night, we crush it between two spoons and suck it into .5 ml water. Our daughter never even wakes up. It doesn't really disove, but rather becomes a suspension. Works great!