A Message to Jonah
A Message to Jonah is a Document in the Rise of the Tomb Raider: 20 Year Celebration DLC Blood Ties. It is actually a voice recording on Lara's phone addressed at Jonah and belongs to the Messages set. It was clearly recorded after Lara's return from Syria, but before Jonah came to meet her at Croft Manor, before the two set out for Siberia.
Note that this is a different but similar phone to the one Lara had in the introductory Cut Scene of the 2013 Reboot. That phone most probably went down with the Endurance and was never recovered.
Sorry for not getting back to you sooner. I've decided to do some research at the Manor. A lot has happened and I need some time to think about what I want to do next.
This old place is filled with memories and secrets. Uncle Atlas has tried to keep me out of here for so long, I don't even know if I want to keep it. But... after everything that's happened, maybe I can find out what it still means to me. If it's worth fighting him for.I'll let you know how things worked out when I'm back in London.