Disney Girls' Docmcstuffins, Elena, Minnie, Fancy Nancy, Jr. Underwear Multipacks Inn Sizes 2/3t, 4t, 4, 6 and 8

What is difference between 4 and 4T?

Am i dumb or does the size chart make no sense? what size is 4, 6, 8? i have a 4t and 3t in my house. what size equates to that?

My daughter fits in 2t/3t and weighs 29 punds would that be true to size

Are they good quality?