I watched the latest episode again and notice this pony running out of the same house that we see Filthy Rich come out of a moment later.

Her fur and mane are kind of the reverse of Diamond Tiara's too. Could she be Diamond Tiara's mother? If so that would make her half-pegasus or something.

Though I guess this was technically in dream land, so maybe Filthy Rich just needs to get his mind out of the gutters.

Are... are we really doing this "random pony = DT's mom" thread again?

4571137
Hmm...very interesting. Very interesting, indeed.

4571143

That could be fun! Maybe Princess Platinum was Diamond Tiara's mom?

4571137
So, you're thinking Rainbowshine is Diamond's mom? Working in a weather factory seems a little odd for somepony married to Filthy Rich...

--Sweetie Belle

4571143
4571155

Well they live in the same house, so...

Two problems here.
1: It was also a dream version of Ponyville, so, not necessarily real in the first place.
2: That's not Filthy's house. It's much bigger, with more land around it:

So either Filthy was dreaming of living in a smaller, simpler home, or it means he was in Rainbowshine's house. Either way, likely not Diamond mom, unless he's dreaming of getting back together with his divorced wife or something.

That said, it could always mean that Filthy Rich would like to be married to Rainbowshine.

4571237 Maybe "Mr. Filthy's" marriage fell apart because he was seeing somepony behind his wife's back?