Jastore Baby Girls Swimwear One Piece Swimsuits Beach Wear with Headband (12-24 Months, Red)

Does this have a built-in swim diaper?

My daughter is just turning 3 and she's about 27lbs should I get 2-3 or 3-4??

My daughter is 2 26lbs and is almost out of 2T clothing, what size should I get

My daughter is 12 months old and currently wearing 18 month clothing, suggest 12-24 month or 2-3T?