So much work to do

I'm having (HAVING) to supervise ST and 2 of his friends, whilst simultaneously keeping an eye on FP who's in a different room. The reason for this scrutiny is that they have ordered pizza and since I have no past information on how close to my mouth they are likely to hold their slices, I am monitoring their regular non-eating habits so that I can be sitting by the right person when the time comes.
Planning, sigh, it's hard work.