The half-heart symbol drawn on the upper lip seems to be one of Big Mom's trait. Adding to that the color "pink", the color of sweetness and, by addition, candies, which the emperor particularly adores, as seen through the Fish-men island arc.
Note that Lola and her zombie are desperate to find someone to marry, and this last chapter talks about Big Mom's daughter destined to be married, with Sanji.
The recurring elements are the lips, the sweet related colors / passion (Pekoms, Tamago's, Bobbin's and even the three-eyed girl's clothes) and marriage.
With that being said, lets move on to another question ; how on earth could Big Mom have so many daughters ? This is mysterious because of two things.
Firstly, they're all girls. I find it strange that it wasn't mentioned that Purin / Purridge (whatever her name is) would be the 35th "child" instead of "daughter". Would Big Mom only be able to give birth to girls ?
Imagine if she desperately wanted to have a boy, and that's why she would have so many children. Now who would be willing to have sex with "this" monster (really, I'm not joking here) ?
Strictly no idea. She could have some sort of weird charming power (although Hancock already has that), force people (ugh) or even be a hermaphrodite, which means having both male and female reproductive organs, thus being able to make babies herself (don't really remember but didn't Big Mom refer to herself as a "man" once ? Or was it a translation mistake ?).
Anyways, this isn't adding anything new to all the theories the net has proposed as of now, and isn't even the main thing I wanted to talk about.
I was wondering if Jewelry Bonney could be one of Big Mom's daughters too.
She has the same pink-color attribute (her hair), the same lips, and the same passion for food.
But something is tricky here, though. We can't determine her age, because of her devil fruit. We'll just ignore that part for now and admit that she would have the age to be Big Mom's child.
Another question that has to be resolved is "Why was she crying when Whitebeard / Ace died" ? Of course, we could argue about the fact that she could have been the fruit of Whitebeard / Big Mom's relation (note : if it were the cause, Weevil could be the main antagonist in a Bonney/BM related arc, which quite honestly would be interesting) or even Ace's waifu, but I'm going to look at it in a different way.
When Whitebeard died, he wasn't the only one to suffer. His whole family was teared apart. "Family", that's the main idea behind all this. Big Mom's crew is a huge family, just like WB's one (her entire crew refers to her as "mama" and the Whitebeard pirates referred to their captain as "father").
Her tears could be interpreted as a form of (extreme) compassion.
But there's a counter-argument to all this. If Bonney loved the concept of family this much, why would she (admitting that she is indeed BM's daughter) change her name ? Cut the ties that she had with her ? Because following this theory, her official name should be "Charlotte Bonney", not Jewelry Bonney.
We don't have the answer, but there could be a reason, explained further on in the story.
Notice that if it turns out to be true, she would share a common trait with our favorite cook ; they both left their family.
Well then, could Bonney be the one that would have to marry Sanji ? I know, he's marrying a girl named "Pudding", but if Bonney changed "Charlotte" into "Jewelry", she could also change "Purin/Pudding" into "Bonney".
This wedding is an arranged one. We know that BM got the idea after Sanji's bounty had been updated (Pekoms mentions a "new mission", and they went after the Straw Hats to capture CC in the first place, not for another reason). My thoughts are that she's simply abusing of his "Only Alive" position.
But then, if an arranged wedding it is, what would the Vinsmokes have to win in it (because in this case, both families would want benefits) ?
Remember, Bonney is important to the WG too.
Considering this, imagine what an union between two "invulnerable" characters would look like.
Following this story-line would allow to introduce yet another Supernova in the plot, without dedicating an entire arc to her.
I've written this quite quickly, just throwing out interesting ideas that could be worth debating.
Please give your opinion, propose counter-arguments.