Fixed Size Columns inside a blog post

I have a blog on quotes and greetings etc. I want to put 3 quotes on three columns of side by side, and I want the size of all three columns a same size.

But the column with shorter text in it is shorter than the column with longer text.

I want the all 3 columns to have the same size and match the size of the column which has the longest text in it. Put extra space below text of the columns which has short text to match the size.