In Czech, expressive forms of family relations and
personal names
are derived with the suffix -ch [x] added to
first syllable of the word,
for example:
bratr > brach, kmotr > kmoch,
Petr > Pech, Matej > Mach ...
I would like to know in which other languages
such or similar suffix appears.
My guess is that it is augmentative suffix
-sko
with expressive metathesis to
-kso
and RUKI change to [-xo].
P.A.