@Gardener: thank you so much!
I've found my Robert on the tree you sent, the one born in 1679. He is the son of Robert at Higher House on their tree. The one I was looking at before was, as you say, the son of Edmund.
By the way, the
https://baslowhistory.co.uk/ website is fascinating! Very interesting indeed, worth a look. I've emailed the owner, David Dalrymple-Smith.
Their tree shows five of the eight children I have for Robert Marsden by his first wife Elizabeth . The tree also shows a second wife Hannah, which is interesting. I hadn't picked up on that.
My ancestor is Joseph, b 1715/6. Where do you fit in?