Hey there!  I know, you're already coaching yourself on how you are going to sell this to your husband.  I've been there.  Just show him the guys in these pictures, okay?  They all thought "this is going to be about as fun as a diaper change" or something like that...but LOOK!!!  Those are real smiles.  Those are dads that walked away a little flabbergasted that they actually enjoyed the time we spent together.  If you can make it to your session, I guarantee we (even Dad) will have fun and the photos will show it.  Don't even try and tell me that your kid is terrible for family pictures...everyone thinks that.  Every kid has a moment, but relax, Mama.  We got this.