On the speech or communications delays front, here's two examples from my life:
My son didn't start using words (instead of making up his own sounds and patterns) until after three. Before that he'd make noises that sounded like words (and were repeated so that you could get a sense for what he meant, accompanied with gestures or staring, etc.) He was obviously trying to communicate, but not in the language we share. He's 6 now and he still makes up words, sprinkling regular English with idiosyncratic word combinations and sounds that he's happy to try to define for you. If he's reaching for a word for something (because he either doesn't find a word that fits or because he's upset at someone), you're likely to get what is considered babble out of him.
I mostly understand him, because we talk so much, but to anyone observing, he ceases to speak English. It's a continuing theme on his progress reports, and something the specialists seeing him would very much like not to hear, but it bothers me very little (since he accompanies it with explanations and gestures.)
I was hyperlexic and read everything in sight, so I talked early (and talked like a 'little professor'), but I also didn't make full sense out of everything I heard and read, so sometimes I combined words eccentrically--for instance, my relatives fish a lot, and I didn't know it was just 'fishing', so I asked if we were going to go 'fish-killing' during a visit. Seems small, but that sort of thing was a pattern in my speech. Sometimes, when people talked to me, they'd run into a 'blank' spot, where I'd lose speech and sit there and stare at them, because they'd asked a question in an area in which I didn't have special knowledge.
Both are a kind of communication delay. In my son's case, it's more a general speech delay, and in mine it was a delay in expressive/receptive language (which he also has.)
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RAADS-R: 181
Eye Expression Test: 19
Alexithymic: Please explain conclusions if asked
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