When I asked, I learned that in Everest's case, he had low muscle tone in his trunk and core, so he was sitting this way for stability. Megan needed to correct this position so that his muscles could strengthen, but she informed me that sitting this way damages any child's joints in their knees and hips.
So why was E sitting this way and what could we do about it?
I asked friends if anyone knew an occupational therapist that could answer a few questions about this (and also E's pencil grasp). I was put in contact with a very helpful OT, Becky McVaugh, who thoroughly answered these questions.
Becky said, "Children who are developing typically usually do this for two reasons. The first could be that they are seeking out sensory input. If you attempt this position, you can feel the stretch that it creates which, for a child whose central nervous system does not register sensory input at the same level as peers, allows the child to be receiving input to their brain about where their body is in space, etc. My hypothesis (based on the grasp) is that your daughter may be doing this for the second reason. The second reason that children do this is that it creates a wider base of support which helps them support themselves better while sitting on the floor. Many children start doing this when they are younger and it becomes an unconcious position for them."
"I see this position frequently in the 0-3 population that I work with and tell parents 100% of the time that it needs to be corrected as it can actually cause damage to the hip joints. For a child that age, I would recommend pairing a verbal prompt such as "fix your legs" with a physical cue at first. After some time, a few days at her age probably, you should just be able to remind her verbally."
Becky then described some alternate ways that E could sit:
If you or your child has spent any time in the classroom lately, you'll recognize the phrase "criss cross applesauce." What used to be called "Indian style" now has a politically correct and kid-friendly name! Everest took it one step further at our home school preschool and added, "Spoons in the bowl," meaning hands should be in the lap, too!
For side sitting, one leg is still folded the way it would be for w sitting, but the other leg is bent in the same direction. Becky pointed out that this is the position that most chronic w sitting children naturally correct to since it still provides "a base of support, but because you are shifting the center of gravity, the hips are in better alignment." Surprisingly, E rarely chooses to sit this way, but when she does, her left foot is usually tucked under.
Just like W sitting has the legs making a W, V sitting has the legs forming a V. E doesn't seem to have to reach as far to play with toys this way.
Is your child a W sitter? Did you even know this was something that should be corrected? A BIG thank you to Becky for being so helpful with information for this post!