(Edited because I wrote this a little too quickly the first time. 
)
I’ve been gone here for a minute - Thomas you have a way of posting topics that are right in my wheelhouse! lol!
A few things could be going on here, but firstly I would not take that draw of blood lightly. I would also advise you to brush up on your self-protection for you and your daughter before you visit there again. There are two things I would recommend specifically - the Shield of Protection ritual I wrote here:
Shield of Protection Ritual - Witchcraft - The Pagan Grimoire Coven
And wearing an object of pure silver (especially consecrated silver - which can either be done by yourself - or by another witch or priest - around your neck. (And for your daughter too.) I can suggest a ritual if you don’t have one.
Now that being said, I actually agree in that it’s not a bad idea to return to the mausoleum. Your relatives resting there will appreciate the visit, and there may be more to what’s going on than just the entity that attacked your daughter. I say not to take the blood lightly because no benevolent being draws blood - and the power it takes for a non-corporeal to do so is actually a lot. Usually it is a sign of an angry restless spirit… but it could also be something worse. Not saying that to scare you, just so you know. If you proceed with caution and do nothing to piss it off, you should be fine… There’s a story there, for sure. I admit you have me very curious!
Cheers and may the divine protect you ~ 