Charlie was an excellent sleeper until we had to transition him out of a crib shortly after he turned 2. Then it was pretty much bedtime battles on and off for a year! Once he was asleep he usually stayed asleep through the night. But the bedtime process could take hours!
In the end we figured out that he was probably napping too much at daycare and not getting enough stimulation there. His sleep improved when he was in his 3's, and greatly improved once he dropped his only nap at 3.75.
Olive is 28 months and she just doesn't seem tired at bedtime lately. She probably has the same issue of not being stimulated enough at daycare with all the cold weather we've had (they haven't been able to go outside). She goes to bed much later than Charlie usually these days, around 9pm or later. She has been a good sleeper since we sleep trained at 16 months, but bedtime has been a bit of a battle lately. Nothing like what it was with Charlie at the same age, and hopefully it doesn't become like that!
How is your 2 year old's sleep? Did their sleep change in their 2's?