The dead included William Ghulam, principal of the GovernmentHigh School in Peshawar Cantonment, his son Tony and daughter Mariab.
The principal's wife was injured in the blast, which left a trail of death and destruction.
Five members of a single family were also killed.
Junaid, a student of first year and the lone brother of six sisters, was critically injured when two Taliban suicide bombers targeted the All Saints Church on Sunday. He succumbed to his injuries in hospital on Monday.
His engagement was due after six months, family members said.
The victims included cousins Zarsh and Samreen, both aged 20. Suleman, the brother of Zarsh, said he was waiting for them outside the church gate when the explosions occurred.
For Master Riaz Masih, yesterday was like every Sunday. He was packing his musical instruments after the Sunday mass when the blast killed him and his two sons, Imtiaz and Bilal.
Former councillor Joseph and his grandson Wajid were also among the killed.
A clean up of the church has began after the deadliest attack ever on Pakistan's Christian minority.
The two bombers struck at the end of a service at the church in Peshawar, the capital of Khyber-Pakhtunkhwa province, which has borne the brunt of a bloody insurgency in recent years.
A four-member probe committee was formed to look into the attack, while the Khyber Pakhtunkhwa police chief was changed and Ahsan Ghani appointed in his place.
An initial report said the suicide bombers were aged between 20 and 25 years.
78 killed, 130 injured in suicide attack on Peshawar church
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