Admiration
On the surface, this is a pretty simple scene. On the left is Hard Candy, a professional hoofball player and all-around celebrity. She's the cousin of the Pop sisters, including little Lolly Pop, pictured on the right.
Lolly, the younger sister of Sugar Pop and Butter Pop, thinks her cousin is the coolest pony in existence, and every time she's in town, Lolly follows her relentlessly. Hard Candy rather enjoys the little fillys doe-eyed admiration, and gladly lets her tag along while she stretches before games and signs autographs.

However, Sugar and Butter are both a little awkward about Lollys admiration of their cousin.
The truth is, Lolly Pop isn't their sister. She was adopted by them as a baby because her mother couldn't take care of her — Hard Candy. Hard was too focused on her professional career to raise a filly, and in the end Butter and Sugar and their parents agreed to take her in instead. But they never really got around to… telling her that. Hard, for her part, doesn't see any issue with it. It's not as if the kid thinking she's the coolest will change anything, after all.

Lolly Pops father is unknown, but Sugar and Butter have a few working theories…

Hard Candy & Lolly Pop were both designed by c-ryptids