Kalista, and her connection to Hecarim

So, I was bored and looking at the information on Kalista that we know of. One of the first things they showed of her was her spear. And I didn't think anything about it at first.

But I've noticed that the spear she fights with looks strikingly similar to the spear that Hecarim uses. They're not exactly the same in design, and Kalista's spear is made of what looks to be souls. Like after her spirit rose she needed a weapon to fight with, and her real one was nowhere to be found. So she fashioned one to the best of her memory.

One of her taunts she says, "Return our spear." And while this could refer to the item the Black Spear she carries or the literal spears that she lodges into her opponents (Though this would make more sense to be said on the use of Rend if that was the case) I think that maybe this is in reference to her spear which was literally stolen. By Hecarim.

We don't know everything about her yet, but we know she was from the Shadow Isles and was betrayed and murdered. In her reveal where it shows her abilities, she's mostly fighting Hecarim. And while this doesn't necesarily MEAN anything, she's also shown fighting Zed and Lissandra. Both of which who are known for their betrayal.

So my theory is that in life, Kalista and Hecarim knew each other in some form. Perhaps they were comrades, or siblings, or perhaps they just both used the same brand of toilet paper. But when the Shadow Isles reached the tipping point (And became what we know it as today) she was slain by Hecarim (or perhaps someone else and Hecarim simply did nothing to stop her death) and had her spear stolen by him.

I meant to ask about this during the Q&A, but I wasn't able to. Any thoughts on this theory?