My 6 yo son does not have celiac disease, but he is allergic to all the grains containing gluten (plus many of the grains that don't). It is not that difficult to feed a child on a gluten-free diet at home. There are tons of packaged foods and baking mixes (cakes, cookies, brownies, etc.) available at Whole Foods, Draegers and even Trader Joes. My non-allergic daughter (10 yo) eats any gluten-free product I bake and rice pasta without any complaint. It's definitely easier to prepare gluten-free foods for the whole family whenever possible.
It is however, much harder to feed him when we eat out and when traveling. I usually bring my son's meals to restaurants and bring a lot of food with us any time we travel.
The other big challenge is social situations where food is shared (which is almost always the case). This is not so much an issue for a toddler, but becomes more of an issue as they enter school. Every holiday, birthday party, soccer and baseball game, scouts meeting, etc., has group snacks. Some kids have no problem with having their special foods instead of eating what everyone else is. But some kids, like my son, really have trouble with it. He hates to be "different" and has even opted out of going to birthday parties sometimes because he can't eat the cake. It's an ongoing social issue that we as a family are still trying to figure out how best to handle.
I hope I haven't discouraged you, because since he has a medical problem, I imagine it's all the harder for them to find a loving family to place him with.