As for the prophet, peace and prayer of Allah be upon him, thighing his fiancée Aisha. She was six years of age and he could not have intercourse with her due to her small age. That is why [the prophet] peace and prayer of Allah be upon him placed his [male] member between her thighs and massaged it softly, as the apostle of Allah had control of his [male] member not like other believers.

Islamic law requires any female to be physically sexually mature to be marriageable (hatta tutiqa'l-rijal). This excludes pedophilia by definition, as the latter is defined as attraction to prepubescent children.