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He built us though then it was not really a sweet experience but as I became more mature I found out what a great and excellent work he did in us and I'm ever grateful.

as I became more mature I found out what a great and excellent work he did

This is often the way. I hope you had a chance to tell him.

I did appreciated his impact, his mentorship, his tutelage but honestly not to the level I would love but he left us too quick to the great beyond. May his soul keep resting in peace.