Peg drawing scale "drift" between identical keyframes

I have a character made up of a series of parented pegs. The scale of the upper peg appears to “drift” between identical key frames… I’ve tried erasing the keyframes and re-making them… cutting and pasting the keyframe… dragging and dropping to extend… and in the end the character (who should be motionless) shrinks in the middle of the span and grows back to the proper position at the end… Any ideas?

So… not sure why my animation was doing this, but I was able to go into the bezier editor and adjust a handle, which flattened out the line and eliminated the “drift”… I leave this here in case somebody else is having a similar problem…