What to do when it isn't your kid?

[ostrich]

I've been watching my two nephews for awhile now, and I have some concerns. Nephew 1 (the 2-year-old) is constantly sick. That doesn't surprise me, since kids get sick all the time. However, whenever he gets sick they remove dairy from his diet. He seems to get better (and misses having milk) but then he gets sick again. I have a strong suspicion he's at least lactose intolerant. Both nephews required their mom (my sister-in-law) to go on the MSPI diet.

Here's the rub: this kid is skinny. Really skinny. Like half of what he should be. He's fine on height, and mentally he's progressing fine. He's active and loves taking care of his younger brother (Nephew 2). Nephew 2 isn't exhibiting any problems yet, but he hasn't been here very long. I guess my questions are:

1. When should I be concerned that it might be more than lactose? "Stomach problems" run strongly in both sides of my family. I'm not exactly sure what to look for.

2. If I do suspect something like gluten intolerance, how do I talk to his parents (brother and SIL) about it? Realize that my family is still new to me being GF and not quite "with it".
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Ostrich :>--O==={

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