16 month old has extreme Diarrhea only in morning...

For the past week my 16 month old wakes up with explosive Diarrhea (out of his diaper, on pillows). But is fine througout the day. A week before this we were at a cottage swimming in the lake. Is this related?

[AnnieBrooke]

If he had something like giardia, it seems like he would have the diarrhea all the time.  Morning diarrhea is more likely to be from him getting a lot of liquid at night -- is he still nursing, or getting bottles of water, at night?

[mum2beagain]

Sometimes my son is like this when he wakes up too. In his case I figured out it wasn't diarrhea but in fact it was a mixture of urine and feces in the diaper that he did as soon as he woke.