When Amy saw Manish,she recalled,"He is the son of the father of my daughter." Who is Manish?

$P$ is the brother of $Q$ and $R$. $S$ is $R$'s mother. $T$ is the father of $P$. Which of the following statements cannot be definitely true?

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 mother of $B$?

$X$ told $Y$,"Though $I$ am the son of your father,you are not my brother". How is $X$ related to $Y$?

$P$ is the father of $J$. $S$ is the mother of $N$,who is the brother of $J$. $B$ is the son of $S$. $C$ is the sister of $B$. How is $J$ related to $C$?

$A$ 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 $P$. Which is a pair of brothers?