Babysitters around here are as young as 12. So I agree with PDT - don't feel bad about leaving S14 to watch the younger ones, and no explanation is needed to H about it.
You also don't have to explain your night out to H, but I understand the desire to avoid the discussion and/or confrontation all together. Could you meet your friend somewhere rather than having him come to the home and possibly cross paths with H?
Me45 W35 M6 T8 D16 SD11 D0 Dec 07: Bomb July 08: Busted! Thread