I remember that some saint claimed that they can see us when we pray for them…but can’t remember who…but I guess what matters is that we do pray for them.
As for your Mom…how much we want to know we are still in contact with our dearest ones…
My Mum died in 1965, but still in some of my worst moments I find myself saying, “Mum, please pray for my boys. Please pray for me.” I think God ‘gets’ the sheer need and trust in those moments we call on those whose love as humans we most relied upon.