The three brothers were waiting for their brides' party to arrive when a missile hit their house.
The attack happened on the first day of the Muslim Eid al-Adha holiday.
Medics and locals officials have confirmed two houses were struck by bombs, killing mostly civilians.
Prime Minister Khaled Bahah spent months working from exile in Saudi Arabia with Gulf Arab allies to fight against Houthi control of the country.
A week-long pause in the fighting was meant to have started on Saturday.
The rebel Houthi movement said it wanted a return to United Nations peace talks, but only after a complete halt to air strikes.
Warplanes from a Saudi-led air coalition bombed a military base in central Yemen controlled by Houthi fighters and their army allies, and a website of the Houthi-run defence ministry said two students were killed at a neighbouring school.
The Houthis' recent gains in Aden have happened despite a week of air strikes.