It is unlikely to be a pain associated with growing. With growth often bone growth does not match muscle growth causing pain. This can be a source of temporary pain but if there is persistent pain this indicates that something else might be the cause. Professional assistance to isolate the cause & treat it is needed.
If there is an isolated strain Osteopathic treatment is effective in removing a mechanical cause for persistence of this strain. Also, the way the child uses their body in the task or other activities of daily living needs to be assessed to ensure a recurrent cause of regular strain is addressed if it exists.