Leah is an excellent photo subject, and loves to sit still for photos (though she doesn't always smile):
It is very rare to get a photo of Elliot actually looking at the camera, and nearly impossible to get one of him smiling.
Getting a shot of both babies together continues to be a challenge and I might have one shot from the past 15 months of the two of them smiling. Here is the best I've been able to do recently (just try taking that spoon away from Leah for the photo. I dare you):
This is far more common: