Allowing your child to engage in a sexual relationship

I'm watching Born This Way (love it, for sure check it out on hulu if you havent seen it) and its about adults with downs syndrome, and the lives they are living. Some of them are in relationships and it shows the parents as well, while they all navigate love, career and sex. It got me thinking how I would be with an adult child with DS who was in a sexual relationship. I believe firmly that if everyone can consent and be safe then they should be able to engage in an intimate relationship since it's one of the most natural things a human can do. I dont beleive people with DS should be deprived that right just because they have DS. I would also be worried about them being taken advantage of, and I would battle that fear greatly. I feel like it would be very conflicting for me to go through since I would want to protect them and also not hold them back from living a full life. My question to you all is how would you feel if you had a child with DS(or if you do have a child with DS) who got into a sexual relationship as a young adult (or even teen)? Would you be okay with it? How involved would you be in the enabling of it (i.e. letting them sleep with their partner in your home, providing protection etc.). Please remember while answering that people who have DS are humans and deserve respect. No shitty or degrading comments/language.