First, let me start out by saying that this is not an 'AW - my kid is a genius' post disguised as a question. I am honestly a little weirded out by this and want to know what you ladies think.
For several months, I've noticed that Nanette has been seeming to sort things by color. For example, I'd leave her to play with some shape sorting blocks and I'd find them matched up, then I noticed that she did this with stacking cups, and now this...
She has since thrown out every single orange and yellow ball, and is now happily playing among only blue balls. (keep it clean ladies )
Also, she prefers to drink out of purple sippys - if I give Maggie a purple sippy, she freaks out and tries to take it - and won't drink out of the pink sippy.
Has anyone experienced anything like this with their LOs? Is it just a weird preference thing, or kinda OCD like? Do you think I should bring it up at her 12 month well baby visit, or am I over reacting over this?
Re: Color sorting at a year?
Very interesting for sure, probably wouldn't hurt to bring it up with the doctor...particularly given that she throws a fit if she doesn't get a purple cup. Probalby just one area she's exceling at early - she must like cool colors haha
And....
...on the blue balls hahahaha
The only thing I can add about the cup though is that when she had her milk/soy allergy, we always fed her out of a purple bottle to keep from mixing it up with Maggie's. I think it's a strong possiblity that she's made some sort of connection there with eating...
I think I will bring it up though, mostly because if I don't, it will eat at me. It just seems strange...but maybe it's just mostly because Maggie doesn't do it that it seems more odd that Nanette does, KWIM?
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Several people that I know who color coded their babies had their kids insiting on that color sippy/plate/etc for years, so that I can totally see.
The rest, yeah, it may be a little OCD, but at the same time OCD isn't necessarily a bad thing
My son has always been very obsessive with his toys. They must be in a perfect row, facing the same way, etc. The best game I would play on him would be to flip a car in a row of cars and see how long it took him to notice 
I'd say just go with it and if she's interested in colors and sorting maybe get her more sorting toys. If your other daughter has something else she likes better (noises, shapes, textures, etc) focus on that. I've always found at that age its better to teach them what they're interested in than to focus on the developmental milestone goals!
***Twin fraternal girls born at 35w6d in 12/2008***