1. Yes, your child will receive treatment, but the effects may be very much reduced. Perhaps there is another way to obtain the DNA sample. Hair is unfortunately not suitable.
2. But another opinion is the DNA, even between relatives, is unique. As relatives, they may have many similarities but there are distinct differences in the DNA. Your siblings may, but shouldn't. The DNA of every individual should be different since just the difference between a male and female should be enough difference to make the signal go to the one within the remote. If someone gets some "cross-talk", there is generally some other reason that the individuals are sharing energy.
For more details, please check this link: