Sen and his three daughters

We can solve this with $4$ equations and $4$ unknowns.

Let $S$ stands for age of Sen,

$H$ stands for age of Hen,

$W$ stands for age of Wen,

and $F$ stands for age of Fen, then:

$S-3 = 2(H-3)\dots 1eq$

$S-3 = (F-3)+30\dots 2eq$

$S= W+47\dots 3eq$

$(W+4)= \frac{H+4}{2}\dots 4eq$

Solving for our variables yields:

$\implies W=14, S=61, H=32, and \ F=31\implies W+S+H+F= \boxed{138}$