Pointing to a photograph,Vipul said,"She is the daughter of my grandfather's only son." How is Vipul related to the girl in the photograph?

$A$ family consists of six members $P, Q, R, S, T,$ and $U.$ There are two married couples. $Q$ is a doctor and the father of $T.$ $U$ is the grandfather of $R$ and is a contractor. $S$ is the grandmother of $T$ and is a housewife. There is one doctor,one contractor,one nurse,one housewife,and two students in the family. Who is the husband of $P$?

Introducing a man,a woman said,"He is the only son of my mother's mother." How is the woman related to the man?

$A$ family consists of six members $P, Q, R, X, Y,$ and $Z$. $Q$ is the son of $R$ but $R$ is not the mother of $Q$. $P$ and $R$ are a married couple. $Y$ is the brother of $R$. $X$ is the daughter of $P$. $Z$ is the brother of $P$.
How many children does $P$ have?

$A$ 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 $D$?

Read the following information carefully and answer the question given below. 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 $B$. Who is the wife of $E$?