Lesson 38. Relatively speaking. 
Have a look at our .Supplement 26 It's obvious, isn't it, that we are a family oriented lot? A word for just every member of a HUGE extended family.
Except for the  ऋकारान्त words, which you have still to learn, the rest are easily declinable.  Supplement 27 tells you how to decline मातृ , पितृ and the rest.
Masculine Words that are declined like पितृ father...     भ्रातृ brother , जामातृ son -in -law , देवृ Husband's brother , नृ man .
Feminine Words that are declined like मातृ mother...    दुहितृ  ( daughter) , यातृ ( husband's brother's wife.), ननान्दृ ( husband's sister), स्वसृ (sister.)
Masculine Words that are declined like कर्तृ .... doer, भर्तृ one who bears or carries or maintains; husband, नेतृ leader, अभिनेतृ actor,  हर्तृ one who seizes and takes away, रक्षितृ one who protects, सवितृ the Sun, श्रोतृ one who listens वक्तृ one who speaks, ¸दातृ  one who gives , विधातृ a granter, a giver, a creator; Brahma.
These words are like adjectives ...convert them into a कर्त्री , नेत्री , अभिनेत्री etc and the whole lot can be made into feminine forms to be declined like नदी ।
If you want to convert them into neuter forms , the words, कर्तृ ,वक्तृ , धातृ... a protector. etc will be declined like... नेतृ  leader 
All of this is just for your information.
                                                                  The exercises in Lesson 38 A will deal with just dear ol' Mom and Dad.

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