If you are talking about actual children, I think these harps would be too fragile. I would suggest selling them to a restorer, or investing in restoration and then selling them, recover your money in any case, and get a couple of sturdy newer harps for your lucky, lucky grandkids.
Every time I cast eyes on the harmonic curve of my 1805/1807 single-action Erard, it lifts my heart. I wish I had those thousands of dollars. Then I go and play my elderly but playable old Troubadour, for which I have affection but not the love I have for the Erard..