Several years ago, at my previous pastorate, a family of 6 began attending our small congregation of 25. They had an autistic teenaged son who often blurted things out loudly (like Tourette's) and at other times would eerily whisper strange things under his breath. The mother, who was single, tearfully explained after the first service they attended that they had been asked to leave numerous other churches over the years due to the way her son behaved, and pleaded with me to allow them to keep attending our church. I told her they were welcome in our fellowship. At the next service we had when the family was not present, I explained the situation to our folks, and asked them to pray for this family, and to try to make them feel welcome among us. We were really glad to have them, what with how small we were. The family faithfully attended for several months before they moved back to their hometown. During that time, let's just say, it made conducting a service (especially preaching!) very challenging and definitely not boring! For us the most important thing was to try to keep the church folks well informed of the boy's condition. The second thing was to exercise a lot of grace, love and patience. The third thing that really helped was the boy's mom was able to help him settle down somewhat, and to keep his outbursts in check to some extent. In my experience, dealing with a situation like this pretty much requires a very committed and very patient adult to supervise them. Without that, it's pretty much chaotic.