"Our brother who is in prison has lost his wife and son while my sister who is in Saudi Arabia has lost her only two children and we don't know how to tell them," she said.
Wanja's younger sister Virginia Wamaitha who had attended the family gathering narrated how her two-year-old girl was snatched from her hands by the raging waters.
"We had met with a view of selling any personal items so that we could raise money to bring home our brother," she said amid tears.
Wamaitha termed the evening as fun as they exchanged ideas before sharing dinner which would painfully be the last for the family.
"We had one of the most enjoyable dinner with our family members before retreating to bed only to be woken by a loud sound before our house was filled with water," she said.
What followed was horror, as the family screamed as the house was swept away by the floods.
Wamaitha said they were rescued after being swept away for more than 200 metres before landing on a tree trunk where they stayed for over two hours before help came.
"The body of my daughter has been recovered. One of those who died was my brother's wife and we don't know where she hails from and we cannot inform the parents," she said.
John Kubai who lost his mother-in-law, a sister and niece said that they were still coming to terms with the tragedy. Kubai said they visited the private mortuary where they identified the three bodies. He regretted that what used to be his rural home was no more.
"After the incident, we received calls from neighbours and we tried calling our parents in vain only to learn that the bodies had been recovered," he said.
A mason, Julius Mungai, recounted how they were woken up by the floods, saying that it was through the grace of God that they survived.
Mungai said that at first, he thought he was dreaming as neighbours' screams rent the air as the water swept everything on its path.
"I was woken by my wife who said that there was a queer sound coming from the hills. I managed to save my three children before our house was swept away," he said.
Joseph Waigwa has been on the forefront in rescuing those trapped.
Known for championing for rights of the poor in the area, Waigwa, better known as 'Jose wa KDF', managed to mobilise tens of youths and rescue more than 20 people.
"I live on the other side of the town and on receiving a distress call, I engaged a few more youths and we managed to rescue many who were stuck in the mud and on trees," he said.
Waigwa said that some youths were nearly swept away by the floods but that did not deter them from rescuing the residents who were trapped.