LCD problem with arduino pro mini

I have recently purchased an arduino pro mini which I have programmed by connecting to an arduino UNO. Programming seems to work fine with no problem when selecting examples for blink or fade on different pins(on the pro mini) but will not work at all for lcd. The same lcd when connected to the UNO with the same program for LCD and the same pins works fine. I tried the blink on different pins of the pro mini and that works ok. I am puzzled about this and dont know what to try next.
Any ideas ?

While purchasing the Pro Mini, why didn't you also buy a USB-TTL adapter for programming?
They're a couple of bucks.
I can't imagine using an Arduino Uno for doing this all the time.