Unfortunately, I am very familiar with CD. I was diagnosed 18 years ago, but probably had it for years before that.
CD is different for everyone. I worked with four guys with CD (3 of them were brothers) and each one was different. They never suggested my symptoms were CD since my case was so different than their cases.
I was/am considered to have severe CD. I'm in remission now, thanks to surgical removal of the terminal ilieum (end of the small intestine right before the large intestine), Remicade every 6-7 weeks, and daily immunosuppressives.
I had to quit working at age 29 on a medical retirement because I was so sick. Don't let that scare you. Like I said, I'm now in remission, I have a great job as a probation officer, and life is good. Except for having to take drugs every day, an IV every so often, and having to get regular blood work, I'm good. Well, that and the hernia straight down the midline of the abdomen thanks to three cuts in the same exact spot. (It's going to get fixed this fall, and then I'll have a flat tummy!)
DO NOT LET MY STORY SCARE YOU! I'm just sharing it to show that a person can be really sick, and have a problem getting diagnosed, but can recover and have a good life after. Like I said, I now work full-time in a job I love. The CD is more of a nuisance now than a death sentence, which is how I felt when I was diagnosed.
If I hadn't been diagnosed and gotten so sick 18 years ago, I'd probably still be in that same career field. CD helped motivate me to return to get my masters' degree, and then to become a Probation Officer. It helped get me where I am now, which sounds really weird.
My CD manifested itself 18 years ago with vomiting. Lots and lots of vomiting, combined with lots of pain. I tend to get obstructions because the inflammation causes scarring in the small intestine, and the scarring then blocks the intestines. When the intestinal contents can't go the regular direction, it has to come out somewhere.
I was vomiting and in a lot of pain, and DH would take me to the ER, as it wasn't just vomiting one time. It was non-stop for hours at a time. No one at the ERs (multiple--5 different hospitals in total) couldn't tell me why it was happening. They'd just shoot me full of demerol and pheregan, and send me home with directions to follow up with my doctor. I did follow up, and had scopes out the wazzooo. (ooohh, I made a funny!) Colonoscopies, endoscopies, etc. I had my kidneys checked, my liver checked, my gallbladder checked, etc, etc. The good news is that my liver, kidneys, gallbladder, etc, etc, were in great shape. No ulcers in the stomach. But I was still sick.
Finally, one night, I was in such bad shape, I told DH I would probably die before we made it 10 miles up the road to the big city hospitals, and told him to just take me to the local, rural, podunk, county hospital closer to our house. Now, supposedly, that hospital was just a rural, podunk, not as modern as the big city hospitals, so we never went there. Not 30 minutes after we arrived, and they'd given me the demerol and phenergan to settle down the pain and vomiting, Dr. David Wipperman was leaning over me, saying, "I think you've got Crohn's Disease, and I'm going to operate in the morning." Finally, I had a name for this thing. After the next morning, I had a diagnosis. He was right. All those scopes, tests, etc, and it's was a doctor's gut instinct and surgery that diagnosed me.
Since that time, I've had more intensive testing through enterocolysis, MRIs and CT scans, and my terminal ilieum was in bad shape. All told, I've had three surgeries, and have lost about 2 1/2 feet of small intestine. Like I said above, I tend to scar in the intestine, and get blockages. At the last surgery, the surgeon said the scarring was so bad, there was only an opening about as big as a pencil lead for the food waste to go through at the end of my small intestine. No wonder I was sick. Thanks to the magic of modern pharmaceuticals, I don't plan to ever get that sick again.
Good luck to your family member.