In a coded relationship, if P × Q means P is the mother of Q, P ÷ Q means P is the father of Q, and P + Q means P is the daughter of Q, what is the relationship of R if P × R ÷ Q means P is the mother of R and R is the father of Q?
If P - Q means P is the sister of Q, P + R means P is the mother of R, and R × S means R is the daughter of S, what is the relationship of Q to S in the expression P - Q + R × S?