How old was your child when you suspected that might be gifted?
My eldest's pediatrician kept saying "99th percentile!" starting when my son was only a month or two old.
Also, strangers kept saying "What an awake baby!" Being a brand new mother, I had no idea what they were talking about, and would think "Well, of course he's an awake baby, I mean he's AWAKE, right? He's not sleeping!"
Finally, my mother came to visit when he was 5 weeks old and SHE said it. At that point, I verbalized what I'd been thinking all along and she explained that "awake" really meant "alert." I still didn't fully get it and she explained that most newborns aren't terribly interested in their surroundings. Then I took a nap while she gave Mr. Awake a bottle.
The next one was born 3-4 weeks early but met all the milestones for alertness, including the one-month ones. He was different though: he wanted to stare and stare at stuff starting around 2 months for faces and 4/5 months for animals/books. He would look up at my face nonstop for ten minutes or more when I had him in a Baby Bjorn carrier when he was only 8 or 9 weeks old (people would comment on it). I used to worry that he was going to give himself a muscle spasm.
He wanted to learn about dinosaurs from an extremely early age (1 1/2? ) but we didn't fully get it until he was around 2.
The next one was basically alert on the day she was born. I think the first one may have been too, but I was way too out of it to notice or comprehend. I finally knew what to look for by the time she came along.
My kids aren't PG (not self-taught readers at age two for example); they're probably high MG or HG. Though if you can be PG at prehistoric creatures, my six year old paleontolgist might just fit the bill. He could learn from BBC paleontology documentaries before he was 3.
Silly stuff: one of my cats is kitty-gifted. He can open doors and drawers (especially if they contain food) and flip things over (especially if flipping things will result in him getting food). He also learned our (cat food-related) slang terms within a few weeks of moving in with us. He's a bit overweight, yet knows exactly how to convince people that he is just a Poor Starving Kitty in need of a good meal.
He also squeaks when you pick him up. This is unrelated to his giftedness, but is darn cute.
How old was your child when, and if, you had them tested?
Haven't had the kids tested yet. We may or may not do this.
As for the cat, we just hide the food in increasingly difficult-to-reach places as he figures out how to reach each hiding spot.
V.