I really sympathise with you Rivergal because I have a 15 year old daughter who is giving us sleepless nights at the moment.

My biggest advice to you is to make sure your daughter is on the pill.
When I was 16 I went out with a lad who was 7 years older than me and I ended up getting pregnant because he refused to wear a condom. Although I thought I was grown up I obviously wasn't mature enough to insist he wore a condom.

I would say no to your daughter staying overnight with him until she is 18.