How did the Prophet, may God’s prayers and peace be upon him, marry his two daughters Ruqayya and Umm Kulthum to the sons of Abu Lahab before the Prophetic Mission, when they were at a young age that could not bear cohabitation?

Ruqayyah, the daughter of the Messenger of Allah, peace and blessings be upon him, was born when he was thirty-three years old. Utbah ibn Abi Lahab married her before the Prophetic mission, and his brother Utaybah married her sister Umm Kulthum. If this is established, then the marriage contract would have taken place when they were young, without consummation. Then, they divorced them before consummation.