$A$ is $B$'s sister. $C$ is $B$'s mother. $D$ is $C$'s father. $E$ is $D$'s mother. Then,how is $A$ related to $D$?

Pointing to a lady,a girl said,'She is the daughter-in-law of the grandmother of my father's only son'. How is the lady related to the girl?

In a family,there are six members $A, B, C, D, E$ and $F$. $A$ and $B$ are a married couple,$A$ being the male member. $D$ is the only son of $C$,who is the brother of $A$. $E$ is the sister of $D$. $B$ is the daughter-in-law of $F$,whose husband has died.
How is $E$ related to $C$?

Following questions are based on the information provided below:
$A \times B$ means $A$ is mother of $B$.
$A - B$ means $A$ is brother of $B$.
$A + B$ means $A$ is sister of $B$.
$A \div B$ means $A$ is father of $B$.
How is $K$ related to $M$ in $R \div M - K$?

All the six members of a family $A, B, C, D, E$ and $F$ are travelling together. $B$ is the son of $C$ but $C$ is not the mother of $B$. $A$ and $C$ are a married couple. $E$ is the brother of $C$. $D$ is the daughter of $A$. $F$ is the brother of $B$.
How many children does $A$ have?

Pointing towards a person in a photograph,Anjali said,"He is the only son of the father of my sister's brother." How is that person related to Anjali?