ADD - kid vs parent

My middle daughter is a bit absent minded.  Sometimes her poor short term memory worries me. I'm not sure if it's a lack of focus or that she truly doesn't remember.  

For example we'll be talking about going to the library and what books to get, and then we'll get ready to go, get in the car and she'll ask where we're going?

I'll ask her to get something and she'll leave the room and come back a minute later without it.  I'll ask where it is and she says she forgot.  

We kiss our kids goodnight in each of their rooms.  Sometimes my husband and I are in the same room at the same time sometimes not.  Very often if we don't go in together she'll say one of us didn't kiss her goodnight.  Not because she's stalking or wants extra kisses, but because she forgot.  

She's eight and maybe this is typical behavior for an eight year old, but my older daughter is so on top of things that she wasn't like that when she was eight.  

I realize these aren't all true ADD symptoms but I did take an online quiz the other day to see if she was even on the spectrum.  I answered as honestly as I could and she came in the low range of possible mild ADD.  Then I saw a link for a similar test for adults so I took it.  I got the same number as her but on the adult scale that put me smack in the middle of the mild ADD category.  I blame the multitasking required of parenting, and my iPhone.  I guess I should work on fixing my own issues and let her be.