Well there are identical and non-identical twins. So, if they were identical, and for some peculiar reason you thought one was "ugly, dull and short", you'd probably think the same of the other.

A better question though, is; why would you describe anyone like that in the first place? Makes you sound a pretty rotten person.

I am taller than my twin sister!

I was born a twin, but sadly my brother only lasted weeks.....but I bet he was the ugly boring one,..I'm so nice

That's crazy but no kid is ever ugly. Period

Depends on if they're fraternal or identical.
There was an Arnold Schwarzenegger and Danny Devito movie about the subject.

paternal or maternal twins? and some kids I knew in elementary school that weren't very pretty ended up hot anyway

Anyone can be dull and ugly if you are judgemental enough

I’ll just ask my crystal ball 🔮

Nah .... I got nuffin.

Khadija where are you from