Advice on how to build a query with partial sums

I need to build a query for the sample data below:

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fte_clave fte_padre fte_porc fte_porc_aux total
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1 1 25 25 50
2 1 25 0 50
3 1 50 25 50

4 2 20 0 40
5 2 20 25 40
6 2 60 15 40

7 3 15 35 60
8 3 15 0 60
9 3 20 0 60
10 3 50 25 60
-----------------------------------------------------------------------
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The table contains only the first 4 fields and I want to build a query that
gets such fields plus a fifth one (total) with the sum of "fte_porc_aux"
for each "fte_padre".

I will very much appreciate your comments.