Hundreds of Ukrainians attended funeral services for the Martyniuk children, including 17-year-old Roman, 8-year-old Stanislav, and 12-year-old Tamara, whose parents survived the attack.
At least 34 people including two children were killed when Russian missiles struck Sumy during Palm Sunday, in what President Trump called a Russian "mistake."
Two Russian ballistic missiles struck the city center of Sumy, around 30 km (19miles) from the Russian border, injuring 83 people, including seven children.
Emergency responders continue searching for survivors after a Russian missile strike demolished part of a five-story hotel in Kryvyi Rih on 5 March 5, killing two people and injuring 14 others.