An oversight

I've already been struggling with the fact that Lillian will have to go to Kindergarden next year, right, I think I might have mentioned it a time or two.  Maybe not.  Let me back up a moment, I started volunteering in the library at school again this year. Started last week.  I almost had a big old break down just watching one of the little girls in the K class.  She was in Lillian's class last year.  She was doing ok, but just putting my child in her place next year, brought on quite a bit of anxiety.  I stuffed the thoughts in another place in my mind and went on about my duties. 

Today, as the aid helped Lillian to me at the bus stop, she said to me..."she is probably pretty wet, she had a lot of juice today" As soon as I picked her up, the smell of poop assaulted my nostrils.  I said, "ewww, and pooppy too."  I get her in the house, go to change her diaper, and find her diaper almost overflowing of poop.  (I can't think of better terms, so poop it is)  I get it, she could have done that from school to home...maybe....except there are defined reddened areas where poop has been on her skin for longer than a two minute ride home.  Now, my child, her skin is sensitive.  She breaks down quickly.  She's red on her lower back where poop has been pressing into her.  I go back in forth in my mind about what to do.  I'm convinced within myself that this is NOT a "just happened" situation.  I decide to email the teacher.  I was nice.  Factual.  I mean, I really am a reasonable person.  I'm not sure if I feel better after the response...an apology...and the words, this was an oversight.  I read on to learn the last time her diaper was checked was 2 when she was found dry.  She gets off the bus at 330.  You can do the math I'm sure.  Oh, and noone smelled it....ok.  I'm trying here people.  I'm trying to be rational. Right now, I just feel disappointment.  How am I supposed to be comfortable with her, a nonverbal child, being in a place for several hours of the day where at least 3-4 people, who work in CLOSE proximity to my daughter, don't notice something like that...and even tell me she is "likely really wet from all the juice she had at snack" ...but we didn't think to check her again for an hour and a half....seriously?  who likes pooppy diapers???  oh me me, me I do....Come on.  Discouraging.  An oversight.  *sighs*  I did also get the teacher's assurance they would check her from now on....thanks.