In April 1940, memorial windows and an altar rail were dedicated at Saint David's Church, Ystalyfera. The article from the South Wales Voice, Saturday 27th April 2018 describes this event:-

Church Dedication Service
Lord Bishop at Ystalyfera

There was a large congregation at Saint David's Church, Ystalyfera, when the Lord Bishop of Swansea and Brecon, the Right Reverend E.W. Williamson, dedicated an East window and altar rails. The window was given by John, Edwin, Lucy and Abram, children of William Williams, The Woodlands, Ystalyfera, in memory of him and both his wives, Margaret and Minerva, and his daughter, Evelyn Robinson Williams, while the altar rails were given by Mrs Lewis, Ty'Rwaun, in memory of her husband, Dr W.J. Lewis.
Reverend J.G. Hughes, B.A., vicar, conducted the service and the lessons were read by the Reverends Idwal Ffread Jones, A.K.C., senior curate, and Canon J.J. Hughes. B.A., Vicar of Pontardawe. Mr Gethin Owen presided at the organ. As the Bishop entered the church, the Ystalyfera Company of the Church Lads' Brigade, under Major A.J. Cross and Brinley Owen formed a guard of honour. Mr Alan Cruikshank was Cross bearer.
The window was unveiled by Mr Gomer Evans, M.A.

Description of Window

The window which is the work of Mr Horace Wilkinson, London is described below:
The subject depicted in the three central lights and the tracery openings above, is the Ascension of Our Lord.
The central light depicts His Ascension to Heaven in a Vesica of Glory. Beneath Him the figure of Saint John, the Beloved Disciple is shown kneeling and looking upwards. The inner side lights are filled with His Apostles and the Blessed Virgin Mary, who with Saint Peter, is shown kneeling. At the base of these three central lights is a label on which are the words: "I ascend unto My Father and Your Father".
In the tracery openings are the letters Alpha and Omega, two Angels with musical instruments as a sign of rejoicing, and in the centre are Angels holding His Crown of Glory and Righteousness.
In the side lights are the figures of Saint John the Divine, with his emblem, an eagle, at the base. Balanced on the other side with a figure of Dorcas, holding a garment typifying her good works.
In the corner of the base beneath her figure is a scroll with the Dedicatory Inscription -
"To the Glory of God in memory of William Williams, The Woodlands, Ystalyfera, and both his wives, Margaret and Minerva; also his daughter Evelyn Robinson Williams"
"This window is given by his children John, Edwin, Lucy, and Abram, 25th April 1940"