i did something i knew i shouldn't have

so last week my friend jill was all stressed out about her kids and her job and everything. she looked like she could use a break, so i offered to watch the kids for an hour or two one night while she ran errands. but when i got there, the house was full of toys everywhere and it felt like chaos. i started cleaning up without saying anything cause who wants to deal with that noise? then later jill comes back and thanks me, but her older kid is all sad and says their favorite toy was missing. turns out i put it away when everything else looked too messy. now jill thinks she lost it or maybe the dog chewed it up. i feel bad cause i know she wanted a break but didn't want this stress on top of it. should i just say what happened? don't know if it's worth making things worse, though.