I have a 22 month old female who is developmentally normal who has been sucking her left thumb during the day and night to the point where there is a thick white layer of dead skin. I recommended gauze and vasoline to cover the thumb. Any good suggestions?

This is a good question because the general ideas behind the discussion apply to many behavioral questions. First, is the behavior a normal one for the developmental age? Yes, of course, we all know that children of this age continue the normal infant instinctual reliance on sucking for comfort and self-soothing. If the behavior is normal for age but exaggerated in amount or degree, as in this case, you can be reassured that the child is not showing serious psychopathology but responding in a normal but excessive way to anxiety which is too strong. One would guess this constant thumb sucking shows a need to self-soothe in a situation of excess tension, either from environmental stress or possibly stress combined with a temperamental sensitivity to stress of whatever kind is going on. It shouldn't be considered a more serious symptom (eg regression) unless there are other behaviors of a similar nature and an over-all reduction in ability to function.

A good rule for a situation like this is to reframe the parents' question of how to stop it by first trying to form a theory (the parents almost always know, if you can ask it right) of why the kid needs to do it. It's safe to assume that toddlers' wants and their needs blur together, and they don't have the cognitive sophistication to plan their behavior. If the parents push them, or respond as if it's a big deal, the kid will pick up on that and the behavior can be reinforced (secondary gain). It's probably not correct to think of a behavior at this age as a habit only, with no useful function.

If the pediatrician allies with the parents in an adversarial position trying to control the toddler, it is counterproductive in terms of results (and unkind to a kid who is already having a problem), and may reinforce an inflexible response by parents who try too hard to do the "right" thing.

Remember that by 22 months most children have stopped being the euphoric, gross-motor giddy babies they were at 12-14 months of age, and really do suffer a significant amount of inevitable emotional turmoil (the "rapprochement crisis" described by Margaret Mahler) relating to the conflict between comfortable dependency and an increasing need to separate and become individual. The urgency of the need for autonomy conflicts with the sense that their "I don't want you to help me!" attitude may drive the parent away. Ambivalence and the beginning of mixed feelings may lead to a deepening of emotional life, but it doesn't feel very good. At a time when a lot of patience and tolerance are needed, parents very often are hurt, do feel rejected and do in turn show some negativity and rejection of the child (maybe in the name of breaking them of a bad habit).

All in all, the skin changes from thumb-sucking probably are not medically significant (although some anxiety habits can be quite damaging) and advising the parents on how to make her stop is probably not the way to go. Find out about stressors, review the parents' expectations and management, and above all, NEVER GET IN A POWER STRUGGLE WITH A TODDLER.

This may seem like an awfully long answer to a simple question. I would love to discuss this more in person if it continues to be an issue.

Yours. Harriet McGurk